4L30E Slipping During 2 to 3 Upshift - Please Help !

[FourWheelTorque]

4L30E Slipping During 2 to 3 Upshift - Please Help !

I have an 02 Axiom 4WD with the 4L30E transmission.
I have gently owned her since day one. She is always in TOD and Power mode.
First tranny fluid change was at 18,000 / 4 years old. I do mostly local trips.

Recently I hit 36,000 and started to notice a rough 1 to 2 upshift and a slight flare during the 2 to 3 upshift.
I took her in to the shop and had the rear pan dropped and cleaned, magnet cleaned, gasket and filter changed and fluid refilled.
Fluid was only a little tinted, did not smell. A little bit of filings on the magnet. Filter was sort of dirty.
They couldn't get the gasket for the front overdrive pan, so there was no change there.
They put in 2 quarts to the pan bolted it in place. Then pumped in 2 more quarts. Then made sure she was level on the lift, started her running. Worked the quadrant twice. Let her idle a minute. Then pumped in 2 more quarts. Pulled the fill tube out of the fill/overflow hole and let her fluid run out till she was only dripping. Then capped her up.
She shifted fine for about 1 week.

Today she started flaring on the 2 to 3 upshift and now slipping on hard acceleration during the 2 to 3 upshift.
No leaks from accumulator seal. No puddles underneath truck.
If shift quadrant lever manually, 2 to 3 seems okay and normal.

What am I looking at here?
Do I need to have them check the fluid level at a certain temperature on an OBD scanner?
Do I need to have them drop the front pan and refill again.
Does this sound like a cracked clutch drum?
Does this sound like a bad solenoid?
Does this sound like I am headed for a rebuild?

Any help deeply appreciated.

[Ramblin Fever]

Sounds offly young mileage for needing anything major.

What type of fluid did they use; if they used anything designed for *newer* transmissions, that could be the issue.

As long as they replaced roughly 6qts of fluid, sounds like the level's right.

However, you're saying issues were present prior to taking it into the shop??

Are you sure the level was accurate before servicing the unit?....what I'm getting at, is if the fluid was low prior to service, it could've started the issue.

There are issues with the range mode sensor causing hard shifts from 2nd-3rd, and needing to be cleaned...but the sensor won't cause slipping conditions.

[FourWheelTorque]

Fluid was Dexron III.

I've had no visible puddles since the first tranny fluid change and she was good for another 18,000, so I'm assuming that the level was okay at the time of the most recent change. The fluid did not look bad or smell bad when it came out. Usually when fluid is low the tranny cooks and then the fluid is dark and stinks. At least that has been my experience with friend's cars and trucks.

The range mode sensor was replaced about three years ago. My quadrant lights illuminate properly when the lever is moved and I have had no bronco bucking or warning lights.

There are many of these 4L30E 's out there in Isuzu's, Cadillac 's, Honda 's, and BMW 's. Someone must have figured out how to keep these things working right. I am really disheartened because I have really tried to take good care of my truck and yet at 36,000 miles, I am still facing the dreaded "Tranny problems."

Any other ideas or suggestions eagerly awaited.
TIA

[SurferJoe]

Fluid was Dexron III.

I've had no visible puddles since the first tranny fluid change and she was good for another 18,000, so I'm assuming that the level was okay at the time of the most recent change. The fluid did not look bad or smell bad when it came out. Usually when fluid is low the tranny cooks and then the fluid is dark and stinks. At least that has been my experience with friend's cars and trucks.

The range mode sensor was replaced about three years ago. My quadrant lights illuminate properly when the lever is moved and I have had no bronco bucking or warning lights.

There are many of these 4L30E 's out there in Isuzu's, Cadillac 's, Honda 's, and BMW 's. Someone must have figured out how to keep these things working right. I am really disheartened because I have really tried to take good care of my truck and yet at 36,000 miles, I am still facing the dreaded "Tranny problems."

Any other ideas or suggestions eagerly awaited.
TIA

I don't remember if you PM'd me or not - I GET A LOT OF PMs! - but usually these 4L units are a little light in the shorts, and they were just a good idea, gone bad when Isuzu was whoring itself out to GM.

Bad upshifts from 2-3 are ALWAYS causing burning and loss of friction material EVERY TIME IT HAPPENS - and it won't go away. Sorry, but you are sliding at a fast pace off the slippery slope already.

You might notice that the 4Ls are not in current models - for a good reason.

The OD rework to put it before the main case of a 3L was a good engineering idea, but it too was never something that worked out in the real world as well as it should have - especially in a 4WD vehicle, but the real bad boy weakness is the Direct clutch pack. This is where your troubles appear to be with your description.

It's weak and rife with problems if even the slightest thing goes slightly wrong. (Sorry for the slight redundancy.) If you hang just ONE shift, then this Direct clutch pack gets eaten up almost instantly - if not sooner.

Every time you turn the key, you are technically abusing the transmission. It's that simple.

GM just had a lot of these 3Ls lying around - converted them to an OD unit and then renamed them the 4L-30E - and talked some of it's ugly-sister companies to put them in their vehicles for a very cheap price.

This marketing coup gave GM refit-engineers something to do other than play with their secretaries, and it emptied the shelves of an obsolete three-speed with Lock-Up transmission in the GM warehouse.

Staying with the GM/Isuzu theme and leaving out the other fish who got hooked into this game, it wasn't all GM's fault - Isuzu needed a way to cut expenses at very un-fortuitous time, cash-wise.

The Isuzu cars were good - the trucks were more so, but they cost too much to produce with all the EPA and CAFE rules and regs and Isuzu had to recount the beans too many times.

With the 4Ls out of their (GM's) hair, it then became the Isuzu dealers' problem, and I personally feel this was a great big reason why Isuzu soured on the US market.

Isuzu was the poor cousin scape goat that could ill afford bad press and the US public was jaded anyway about things GM, what with the GM/Diesel Cadillacs/Oldsmobiles/Pontiacs/Buicks fiasco, and this just carried over I feel to Isuzu.

Even Joe Isuzu gave up trying to sell them.

[FourWheelTorque]

Thank you for the history lesson SurferJoe. It was informative and also dismaying.

What would you recommend as the best plan of action to diagnose and repair my Tranny?

TIA

[Ramblin Fever]

Recently went to an Isuzu dealer for some parts and was talking to the head mechanic....he was saying that for whatever reason, he sees thousands of the 98+ model years with the 4L30 in his shop for repair more then he's ever seen the 97 and under years.

He had no explanation as to why. However, if you read thousands of posts of failures on here, it's generally on the newer Isuzu models rather then the older models, even though it's the same transmission.

I've had 2 first generation rodeos with the GM 4L30E transmission, one is pushing 325k, the other is sitting at 200k, both have original auto transmissions without a single hiccup. And both these trucks have led a life of heavy towing, off-roading, daily driving, etc.

Only thing I've ever done is change the transmission fluid every 10k miles.

It's very hard and sad for me to see an owner with only 36k miles having issues. That said, I will say there appears to be thousands of other actual chevy truck models with 4L60, slightly bigger sister, that I see having constant issues too.

[FourWheelTorque]

I really want to save her. With the low mileage I do, even if repairing her only lasts another 36K it would mean another 9 years of service for me. My mechanic says he has a good Tranny shop, but I want to know what has to be done in order to get it done right. I've read too many stories about Isuzu owners who have the Tranny rebuilt and it does NOT work right afterwards and they end up junking the Truck. I can't financially afford to do that, and I certainly do not want to. There should be enough of the 4L30E 's out there to find someone in the shop who knows how to do it right. Forget about my local Isuzu repair place, they are in my opinion and the many irate other customers I have met there, awful. The nearest other Isuzu repair place is 35 highway miles away and I know nothing about them. So even though I'm still under warranty, I'm gonna pay for the repair out of pocket, just to get it done right. But I would like to know what the process should be.

TIA

[Ramblin Fever]

I hear you....I feel the same way should mine ever go out. Even though my truck is 13yrs old, there's no rust, dents, etc and the truck overall's in superb condition.

How many miles do you put on a year?

Right now, for the last 3yrs, I've been averaging 5-7k...sometimes I wonder if it's the sitting that causes issues.

[trooperbc]

....

So even though I'm still under warranty, I'm gonna pay for the repair out of pocket, just to get it done right. But I would like to know what the process should be.

TIA

still under warranty...then do take it to the dealer. i believe they would put in a factory rebuilt unit shipped from isuzu, or perhaps even a new unit.

you can easily find out the information by talking to the service managers for those two dealers AND by calling the appropriate isuzu district/regional/whatever office, talking to whomever gets to approve these things. you can lobby that individual, not taking no for the final answer, and get what your warranty calls for. the replacement will also be under warranty.

this has too many advantages to you to ignore imo.

good luck
//bc

[SurferJoe]

Just a note:

I rebuilt warranty bench units for Chrysler, Toyota, GM, Honda and even Subaru when I had my own shop, even Ford with their infamous AODs and E4ODEs.

Most times the dealers provided me with the official parts to be used in the units.

I even found that The Great Honda had mis-designed their rebuilder's pack o-rings with 2.3mm diameters, and I secretly had the correct sized (2.0mm) rings made by a jobber for me and all my units worked while theirs did not - at least until they tore one of my units apart and found their error. I never told them, and I had pretty much an exclusive for over a year until they caught on and skunked me.

There are other war stories I can tell.

Getting a "factory rebuilt" does NOT mean that it was done in a factory. It only means it was done by a contracted shop that built them FOR the OE dealer.

The biggest problem is that the factory will not authorize any parts that are not from the factory's list of suppliers. The parts they authorize can be from short-run facilities that make a part that the dealer (naturally) did NOT make in the first place. Sadly, this leads many people astray believing they are somehow getting superior parts and pieces, when in reality they are not.

The parts will be as good as the original design, but HEY - they failed so why install parts that failed early or blew inappropriately the first time all over again?

Beside the original clay mock-up and the CAD work and the gluing on of an iconic logo, there is very little that the factory actually makes - in fact the factory is just a large assembly area where conglomerated parts are assembled into a finished product.

In a long-ish tirade, if I were to make another one - I'd tell stories about these parts and some of the third-party jobber shops that make them for so-called auto manufacturers. Today is not a good day for me to go into that detail. I don't feel well and the medications are not working. This might also cause me to be somewhat disgruntled sounding and not in the best of moods. Sorry, in advance.

Don't get your hopes up for a "new" transmission either. Almost 100% of the time, the only way to get a new transmission is to have it wrapped in a new vehicle. There are exceptions (there's always an exception somewhere), but I seriously doubt the existence of a new 4L for warranty replacement in your vehicle.

Yes - the latter 4Ls have troubles, and it's the bean counters again.

However - if you can find a Mom-N-Pop transmission shop that has been in business for more than a couple of years and have a current ATRA certificate, then that's where I'd go.

Stay out of large chains, name-branded shops and absolutely stay away from dealers. I rate them just 1/2 step higher than AAMCO - which I personally hold in great derision as bottom feeders.

Talking to the service manager (who has likely never held a wrench or broken a fingernail) is an act of self-delusion and technically a form of self abuse. They run interference for the so-called mechanics in the back, protecting them from angry and hostile customers. That's their job.

I also doubt seriously if you can find a guy with dirty hands that can be allowed to talk to you at all anyway. You might follow one home and grab him as he gets out of his personal car in his driveway and try to get some info off him - but he might be armed and hostile from getting screwed over by the shop foreman when he lost his flags for the day.

And - of course - any replacement unit the dealer gets and installs will be a continuation of the original warranty - not a restart with a new expiration date. There is no Tooth Fairy either.


Of course, that's just my opinion.

[FourWheelTorque]

How many miles do you put on a year?

Only about 4k.

still under warranty...then do take it to the dealer. i believe they would put in a factory rebuilt unit shipped from isuzu, or perhaps even a new unit.

you can easily find out the information by talking to the service managers for those two dealers AND by calling the appropriate isuzu district/regional/whatever office, talking to whomever gets to approve these things. you can lobby that individual, not taking no for the final answer, and get what your warranty calls for. the replacement will also be under warranty.

this has too many advantages to you to ignore imo.

I know you are trying to protect me here and I do very much appreciate the Good Counsel, but whatever damage may be inside my Tranny has got to be less than what took place inside a rebuild before it was rebuilt. The chances of me getting a new Tranny without going through several bad rebuilds is pretty low. I have babied my Truck and most folks abuse and neglect their rides. Anything that is refurbished is usually just fixed enough to pass the barest minimum standards of quality. I have read many posts in forums like Edmunds from owners who had rebuilt Trannys put in and the results were oh so bad and the company would not make good. There's the phone calls, the lawsuits, the threats. Then they dump the car or truck as a trade-in and some other poor slob buys it and gets stuck and dumps it. It becomes like a disease which is passed around. It is an insanity I will not subject myself to. The few times I have been to small claims court, the majority of cases being called were the car dealers who butchered the owners cars beyond repair. Since Isuzu Passenger is "morte" it would be even harder to get any satisfaction. I'd rather take my chances with a Tranny shop that has a good track record and get mine rebuilt right. The Isuzu repair near me is so horrible in my opinion based on my prior experiences with them that I would not even let them put air in a bicycle tire for me. The other Isuzu repair I have no idea about, but it is 35 miles away on the highway and it is a traffic filled trip, so if anything goes wrong it is again a mess.
Please do not be offended. I mean no offense. I have just had bad experiences and have read even more. I don't want to battle anyone, I just want to get my truck fixed right. Years ago I tried getting a radio fixed at a car dealer whose brand I will not mention. After 7 trips to 3 dealers some 20 miles one way away and 3 rebuilt radios later I still had no working radio. I could not take any more time off from work to fight about it. Can you imagine, a stinkin radio and I could not get it fixed. That's why I found a great independent mechanic and have him do just about everything for my trucks. Please excuse my diatribe.

[FourWheelTorque]

Took her in to the mechanic and told him what was going on.

He suspected that she wasn't hot enough when he let the fluid run out after filling - overfull. Brought her up to spec'd temperature and opened the fill plug. About a pint ran out. He said it smelled like older Tranny fluid, not new. Capped her and took her for a ride. No slipping.

But she still has an intermittent flare on 2 to 3 upshift.

Printed out the procedure from ShopKey on how to pressure test for flare problems and possible causes.

Mechanic says he will get overdrive pan gasket and will drain both pans and refill both pans with Valvoline Dexron III instead of the Wolf's head Dexron III H/M just in case there is some floating gunk still in the fluid because the overdrive pan wasn't emptied. Then we'll see if she still flares. If she does the next thing we'll try is the pressure test.

Anyone ever do pressure testing on the 4L30E ?

TIA

[Ramblin Fever]

Hmmm....it's very rare to overfill one of these.

Make SURE your mechanic does NOT use Valvoline *maxlife* Dex III, there's something in that particular ATF that does cause havoc with these transmissions.

The only fluid I've ever used is Castrol Import Dex 3

[FourWheelTorque]

Thank you Ramblin Fever.

I'll warn him off the Valvoline and I'll get the Castrol myself.

I do not find the exact name you wrote. The closest match is CASTROL IMPORT MULTIVEHICLE. Here is the url with the specs...
http://www.castrol.com/castrol/sectiong ... Id=7028224

Is this the one you use ?

It's so strange that some brands of fluid won't play nice in the Tranny.

Just another Isuzu ecentricity I guess.

Thanks again.

[Ramblin Fever]

yeap....that's the one. Keep us posted.

You're going to need around 6-7qts if he's doing both pans.

[FourWheelTorque]

Thanks for getting back to me so quickly Ramblin Fever. It is much appreciated.

I'll keep you folks updated as best I can. Until I get this all straightened out, I am going to set the Tranny to regular mode instead of Power to lower the shift points and I'm going to be very light on the gas pedal.

Regards to All.

[Ramblin Fever]

You know...honestly..I've never understood, (though I've seen others here who have done it and recommend it), why most run their auto's in powermode on an every day occasion.

I live in very high altitude country, and have for nearly the entire lifespan of both my automatic Rodeo's, I ONLY use the powermode feature for climbing a serious incline, and/or if I'm towing the boat and starting up a mild incline and need the extra rpm's for the gusto.

I've never used the powermode for daily driving, even with mild hills, which for Colorado, would be around 7-10,000ft elevation.

I know longtime Isuzu mechanic specialist, JLEMOND, IIRC, has also stated that he uses his in every day type driving too; obviously it gives good results.

I've just always felt that it can actually make the transmission downshift more often; although it does keep the pressure higher, which is a good thing...however, I don't think the more frequent downshifts in every day flat-land driving situations is always a good thing.

I too have always babied these auto's; as I do with my cummins and toyota automatics too.

[FourWheelTorque]

SurferJoe my apologies for the delay in responding to your April 25 post. My OS and browser are old and webpages do not always layout properly on IE6 so I did not find your post until today. I hope you are feeling better. Your insights from the rebuilder's view are very welcome and do sync up with my experiences as a customer. In all things whether they be mechanical, plumbing, law, medicine, etc., there are saints, demons, and a broad spectrum in-between. If a person is fortunate to find a master craftsman or craftswoman, you must hold onto them for dear life as they are hard to come by.

Ramblin Fever I can't speak for all Power mode users, but I drove a stick for many years and am used to winding my engine into the middle of the torque curve before upshifting. The early upshifts that most modern auto trannys do may save gas, but when you try to accelerate it feels like the engine is lugging until you finally get a downshift which usually takes too long in most vehicles. As a consequence, if you need to hit the gas in a panic acceleration situation which I have had the misfortune to be in on occasion, standard shift patterns lead to some very nerve racking pauses before the downshift. Power mode does not turn a 4000 pound beast into a rocket, but it does give you an extra safety margin in that circumstance, which I treasure having. The 4L30E may have its disadvantages, but it has never locked me out of a downshift at too low a speed and left me desperately trying to accelerate in too high a gear as some other auto tranny boxes have done to me.

So far, in standard shift pattern if I keep my rpm's below 2100 for upshift, I get no flare. Flare only occurs at 2100 and above in both standard and power mode. Obviously this also means no flare with gently acceleration, and flare with hard acceleration. I also notice when she is cold no flare at all. The flare occurs after driving a few miles and she has warmed up. I've got the Castrol. I'm waiting for the shop to get the gasket for the front pan.

About 3 years back before Isuzu imploded, they updated the firmware for my 4L30E. Does anyone know if there was a second firmware update that I might be missing ?

TIA

[Ramblin Fever]

Oh I agree that the powermode feature is definitely awesome and it comes in great handy.

Just saying that personally with being exposed to moderate traffic areas, I've never had the need to use it on a daily driving basis.

[evil01rodeo]

We bought our Rodeo with 43,000 miles on it roughly 6 years ago.. I can think of about 4 times I used power mode.

We're up over 160,000 miles now and aside from replacing the accumulator piston cover (and using wal-mart trans fluid) we haven't had any trouble with the transmission.

If there's something wrong with it, it's not going to behave no matter which snake oil you use.

I suspect you have seals inside the transmission that are seeping / leaking due to neglect.

Yes, I said neglect. I put 4000 miles a year on my feet, and I'm a fat lazy desk jockey.

Drive the poor thing.. Don't use power mode unless you need it. Let the transmission do its job like it was meant to.

If anything, put a quart of Lucas in it with the castrol and drive the wheels off the thing. Take a road trip or something. It needs some miles.


Reminds me of a guy I knew... he bought a ZR1 Corvette back when they used that weird DOHC engine..

It never got driven, sat up on blocks in his garage for years..

he went and took it down to drive it, and the thing ran like absolute crap.

All the o-rings and seals had hardened in a slightly oval shape from the weight of the components sitting on them, so they all leaked as soon as it got warm.

I don't know if you just drive it like 5 miles a day or whatever, but that's not enough.

Heck, we put around 20,000 a year on ours and aside from the rust it's been flawless.

..well, that and the engine deciding it was going to snap the cam alignment pins and frustrate me for 2 weeks.

[Ramblin Fever]

Have to agree with you. I've read more then once that NOT driving a vehicle is harder on it then actually driving it.

[SurferJoe]

Let's shake this POWER MODE thing around a little bit.

What it actually does is jack up the line pressure and makes the shift points a little later (higher RPM). On some units it also keeps the TCC from applying - but that's not a 100% situation.

OK - more pressure and higher RPM for a shift SOUNDS LIKE A GOOD THING! Nope - I don't think so, Al.

What you are accomplishing with the higher RPMs is that the engine may be more 'on the cam' and producing more torque or horsepower - and then you ask for a shift? That is not usually conducive to long wear of the unit for several reasons -

(I am going to just one place with this tirade, so you should know that there are a few other to consider too and this is not the ONLY scenario.)

One set of parts that don't like sustained pressures are the annular seals in the stators and rotating shafts that are carrying command pressures to the individual clutch packs. Keeping the pressures high and for long times places a tremendous amount of premature wear on the rings, the upper and lower sealing areas of the shafts and housing upon which they ride and the sidewalls of these annular rings at the same time.

They literally eat the walls away (a form of brinneling) and force nicely machined surfaces into bad wear patterns and loss of sealing integrity.

It's a bigger problem when the ATF gets a little bit abrasive from flaked-off friction material and tiny metal particles: they just act like sand going through your Timex.

This bad wear pattern shows up when the fluid's cold and has a slightly higher viscosity - it can better seal the rings that are leaking and assist the shift points.

But this is a very slippery slope! After a while - the cooler ATF creates the only time the unit actually acts correctly and gets worse when the fluid gets to normal temps!

It's not the end of the world - but using POWER MODE all the time is putting untoward wear on parts that are becoming more and more expensive with the increasing age of our vehicles.

The ;problems are that these stator housings are getting rare and as far as I know - there are NO third-party machinists making repair kits for hogged out housing like for the GM Hydros and other, newer and higher count transmissions.

You're flogging an orphaned mule here to destroy it with not much hope for repair or NEW parts from the factory much any more.

If you have several donor vehicles, then by all means you can afford to wear things out faster than normal - it's a pay-for-play situation.

I wouldn't poke the bear with a stick though.

SIDEBAR - even pick-up trucks have very lightweight transmissions and power train related parts - the logic behind this is that a pick-up truck will only be actually carrying workloads about 8-10% of the time it's used and there's no need to build them any heavier for the 2% of the people who really carry the weight and need to power and reliability.

Somehow the bean counters though that adding a POWER MODE might satisfy people's Freudian Oedipal concepts and also be keeping the unit running long enough to get it off warranty at least.

That was then --- this is now.

[Ramblin Fever]

I always wondered if there was a bad catch to using power mode.

Glad I've only used it when really needed.

So....question is, *should* I even be using it when climbing mountains, or towing, or should I just let the truck (transmission) do it's own thing?

[SurferJoe]

I always wondered if there was a bad catch to using power mode.

Glad I've only used it when really needed.

So....question is, *should* I even be using it when climbing mountains, or towing, or should I just let the truck (transmission) do it's own thing?

Some units are a little finicky that way and need the ECM/TCM to have full control of the shift points and TCC lock-up when it senses that the unit is overheating or has some slippage.

The only thing I'd use POWER MODE for is actual towing and perhaps bucking a huge head wind, etc.

It will allow some extra RPM and a little more ponies to help you hold your own against hills/wind/heavy slogging through sand or mud.

We'd all like to think we are smarter than a transmission - but we don't get the readouts the ECM does and can correct them as it is programmed.

Your results MAY vary and you can indeed get away with a lot of things that seem wrong and perhaps dangerous to other people.

[vafiatx19]

Sorry to hear about your problems. I too am having similar problems. After a lot of research and talking to many service managers and a very highly recommended independent transmission shop (specializes in BMW) I found out that the later models especially mid 2000 and up have a lot of electrical issues. Trans shop owner said 90 percent he has found problems related to wiring or ecm on these harsh shifts. Of course you are aware of the mode switch, but the wiring becomes a problem due to being near a lot of heat. Next the wiring to the unit and ecm is such a small gauge around 20 awg. Heck I have a 30 year old Italian car that the smallest is 16 awg, this is awful small and easy to break or just corrode inside insulation. Isuzu service manager which is now a KIA dealership said the wiring on these is a living nightmare and being around 10 years old brittleness and corrosion is occurring. On mine finally found out wiring harness is bad unfortunately the 2000 rodeo/â€