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Trooper 4L30e Transmission Issue, won't shift out of 1st.

32K views 35 replies 11 participants last post by  Heather L. 
#1 ·
I found a Trooper I really want to buy, as a light duty offroad/camping vehicle for our family of 4. It has everything I want (well, no sunroof, but hey you can't have everything :) ) but it has a transmission issue. I looked here but could not find a thread with these particular symptoms

Here is a little background, 1999 Isuzu Trooper, current owner (who appears to be a very honest upfront guy) bought it about 3K miles ago. After putting a a couple thousand miles on it, the tranny started to give him problems. He had it replaced with a used transmission that worked fine and then started giving him the same problem right after the 1K mile/90 day warranty ran out. I did some research on the the Trooper/4L30e tranny and after reading this thread,

http://forum.planetisuzoo.com/viewtopic.php?t=1707

I was hoping it was the range mode switch (RMS) problem and I went to go see it today with a plan to hopefully fix it and buy it.

When I got there I took it out for a drive and here are the symptoms. It will go into reverse just fine and work, no issues there. When you put it in D, it will go just fine, but never shift out of first. I tried starting in D and shifting up and down through the gears, but it will never shift out of first. I also tried starting out in 1, 2 and 3 and again it always started in first and remained there. I did notice that when I revved it out a bit (30 MPH or so) and let off the gas (but not all the way), the tranny would seem to disengage and the RPMs would rise. When I let off the gas a little more, the RPMs would fall and the tranny would reengage. This was not buttery smooth, but I wouldn't describe it as harsh either. Somewhere in the middle of all this manual shifting the "Check Trans" light came on. The whole time, the gear indicator light always indicated the correct shifter position.

I got back and described what happened and he said that is exactly what he has experienced, though he had never had "check trans" light come on.

I then asked him if he had looked at the range mode switch. He said that the range mode switch and the harness from the transmission to the PCM had been switched out but that he thought they were used parts. At this point, given the symptoms (lights indicated correct shifter position) and that the RMS had been swapped out, I no longer thought the RMS was the culprit, but I asked him if he would let me take a look at it. To his credit he did, so I got my tools out crawled underneath and took it out. It definitely was a used part, as it must have been more than a 1k miles old. I opened it up and it didn't look particularly dirty, but I cleaned it anyway, put it back on and went for another test drive. Same identical issue as before. The only difference was this time the "Check Trans" light did not come on at any point.

He did not say who replaced the 1st transmission, but he did say that he has found another used transmission and that Aamco quoted him $450 to install it, so that makes me think he used Aamco to to install the 2nd transmission. Based on stories I've heard about Aamco, I'm not convinced his 1st transmission was bad. I'm thinking it's something electrical, because I have a hard time believing that a 2nd transmission went bad with the same symptoms 1K miles later.

Here are a couple of other things that may or may not be related, so I'm going to include this info as I have no experience with Isuzus and their quirks.

He has a 1 inch lift that enabled him to install oversized tires without rubbing (305/70/16). I do not know if the lift/tires were installed before the first transmission failure or in between the first and second failures, I need to ask him this.

The Trooper had a newish battery, but it was dead because it had been sitting so long, so we had to jump it. After jumping it and running it for a little while and test driving it (10 minutes total), the battery would not charge enough to restart the engine, but it would work the power door locks. In my experience, 10 minutes is generally enough time to charge a good battery to be able to turn the car off and restart it almost immediately when the charging system is working properly (unless it's a diesel).

I would REALLY like to buy this Trooper, so any help would be MUCH appreciated. Thanks!!!
 
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#2 ·
It probably is the range mode sensor....those things get dirty and clogged and it messes everything up. Also AAMCO probably has no Idea how to put fluid in these tranny's. I would check that also.

When you put it into drive does it engage into gear right away or does it take a couple seconds???

Did you try and press the winter button which starts the car off in 3rd gear. If that doesn't work then its prob range mode.
 
#3 ·
jwood1016 said:
It probably is the range mode sensor....those things get dirty and clogged and it messes everything up. Also AAMCO probably has no Idea how to put fluid in these tranny's. I would check that also.

When you put it into drive does it engage into gear right away or does it take a couple seconds???

Did you try and press the winter button which starts the car off in 3rd gear. If that doesn't work then its prob range mode.
I don't think you read my whole post (I know it was long, sorry). :)

I took the range mode sensor out and it was old, but not that dirty inside. I cleaned it out anyway, and re-installed it and had the same exact issues. I don't remember it taking particularly long to go into gear. I did try the winter button and it did nothing.
 
#4 ·
A dirty range mode sensor won't cause these symptoms.

Sounds like the tranny is either low on fluid, or not rebuilt correctly.

Also, check the volt output of the alternator, if it's less then 14 the transmission WILL behave badly.

305/75 r16 is a LOT of tire mated to the 4l30 transmission; almost too much.

I run a 265/75 r16 on this same transmission and would never opt to go bigger.
 
#5 ·
When you tried Winter Mode with Drive selected, did the vehicle move or did it remain stationary?
___________________________________
01 Rodeo Sport Ironman 4X4 V6 133K miles
01 Rodeo Sport 4X4 V6 48K miles
02 Rodeo Sport 4X4 V6 64K miles
 
#6 ·
Ramblin Fever said:
A dirty range mode sensor won't cause these symptoms.

Sounds like the tranny is either low on fluid, or not rebuilt correctly.

Also, check the volt output of the alternator, if it's less then 14 the transmission WILL behave badly.

305/75 r16 is a LOT of tire mated to the 4l30 transmission; almost too much.

I run a 265/75 r16 on this same transmission and would never opt to go bigger.
That is exactly what I thought after driving it, but I was already there and it was worth a shot. :)

These are 305/70/16 not 305/75/16 which are 32.8 inches compared to your 265/75/16 which are 31.6 inches. You can see the difference here,

http://www.miata.net/garage/tirecalc.html

Not a whole hell of alot bigger, but I do get your point.

Buster28 said:
When you tried Winter Mode with Drive selected, did the vehicle move or did it remain stationary?
When I put it in Winter Mode I was hoping to force it into 3rd gear, but it just ran in first.

Thanks for all replies to everyone!
 
#10 ·
There are 2 plugs on the Transmission fluid pan. One is obviously the drain, the other, a step up on the pan, is the plug to check the level.

Checking Transmission Fluid Level
and Condition
Checking fluid level and condition (color and odor) at
regular intervals will provide early diagnosis information
about the transmission. This information may be used to
correct a condition that, if not detected early, could result
in major transmission repairs.
IMPORTANT: When new, automatic transmission fluid
is red in color. As the vehicle is driven, the transmission
fluid will begin to look darker in color. The color may
eventually appear light brown.
A dark brown color with burnt odor may indicate
excessive fluid deterioration and signal a need for fluid
change.
Fluid Level
When adding or changing fluid, use only DEXRON )â€"III.
Refer to Maintenance and Lubrication in General
Information section for maintenance information and
servicing interval.
CAUTION: DO NOT OVERFILL.
Overfilling will cause foaming, loss of fluid,
abnormal shifting and possible damage to the
transmission.
1. Park the vehicle on level ground and apply the parking
brake firmly.
2. Check fluid level with engine running at idle.
NOTE: Be sure that transmission fluid temperature is
below 30C (86F).
3. Move the selector lever through all gear ranges.
4. Move the selector lever to “Parkâ€
 
#12 ·
hi,
im having what appears to be exactly the same problem,

i just bought mine a month ago working perfectly
mines a 2002 Model,
ive just done a complete fluid flush on mine as it was as black as sump oil when i checked it,
after a replace of the fluid and filter still no better,

checked and cleaned the Mode Switch even though that appeared to be in working order,

Winter mode button also does nothing
slight pull but not enough to move car

it appears to click into gear and just starts to rev its like the clutches dont engage

so now my question is what would be the next thing to try? any suggestions would be great
 
#13 ·
Well, the Trooper I was looking to buy does go into D, but it will not shift out of 1st gear. I talked to a transmission guy I trust and as soon as I mentioned "Isuzu Trooper" his face wrinkled and he said "that 4L30e is a very finicky transmission." After describing the issues he said he would take a look at it for free (all the stuff he can check without taking the tranny out) so I might do that. Just can't decide if I want to spend $150 to get it towed there and then have him tell me it needs a $2200 rebuild. Decisions, decisions....
 
#14 ·
I THINK YOU SHOULD LOOK FOR ANOTHER TROOPER. DONT NEED THE PROBLEM. CK AROUND :idea:
 
#15 ·
totten said:
I THINK YOU SHOULD LOOK FOR ANOTHER TROOPER. DONT NEED THE PROBLEM. CK AROUND :idea:
I know what you mean.....but the rest of this one is SO clean....leather interior and low miles, brand new tires, etc etc....the tranny is the only issue and for the price even if it needed a new tranny, it would still be a good deal....but you are right about not needing the problem. :)
 
#16 ·
You state that when you tried Winter Mode, the transmission stayed in 1st gear. Member hewball posted on 9/9/10 that his transmission is stuck in 1st gear also but when he tried Winter Mode the vehicle did not move at all. Since Winter Mode forces the transmission into 3rd gear, it is noteworthy that although you both have the same initial symptom, forced 3rd gear selection produces a different result. The fact that your transmission stayed in 1st seems to indicate that the shift solenoids are not working at all, in which case you may have an electrical problem.
In 1st gear the 1-2/3-4 shift solenoid is de-energized and the 2-3 shift solenoid is energized.
In 3rd gear the 1-2/3-4 shift solenoid is energized and the 2-3 shift solenoid is de-energized.

_____________________________________
01 Rodeo Sport Ironman 4X4 V6 133K miles
01 Rodeo Sport 4X4 V6 48K miles
02 Rodeo Sport 4X4 V6 64K miles
 
#17 ·
Buster28 said:
The fact that your transmission stayed in 1st seems to indicate that the shift solenoids are not working at all, in which case you may have an electrical problem.
just for reference, this is exactly what mine is doing too, it revs and holds first, then clicks into next gear and just rev's free no pull from the transmission

cheers Hewball
 
#18 ·
for those interested, ive have had my 4l30e apart for a rebuild and the 2nd gear clutch's resembled more of a steel plate than a clutch and the few with clutch left were cooked from the heat of metal on metal, so heres hoping when i finish the rebuild and put it back in its all good again
 
#19 ·
Ok I have read this post and I am having the same issue just started this morning I put it in winter mode and it goes to third but just revs then threw it into power mode and goes to first but wont change gears how likely is it that the flewed is low and that the trans is not toast I just replaced it with a junk yard trans and made sure it was full when I pulled it off the lift and this happend out of no were. I have replace three trans due to shelling out and crappy rebuilds but this just happend no normal warning signs pleas let me know what you all think.,
 
#20 ·
So I turned to this forum because I too am having an issue with my Trooper not wanting to shift right. I have a 97 Trooper with a 2" OME lift and 265/75/16s. I bought it about 3 months ago. The guy I had bought it off of said he had just had tranny serviced. Here I am about 1200 miles later and boom, all of a sudden my truck is not wanting to shift out of first gear very well. I tried the putting it in winter mode thing and noticed that not only does it not go into 3rd gear, but the light does not come on at all. Also I have tried putting it in 2nd and 3rd gear to see if they would start out in those gears and its like its in drive. It stays in first gear. My questions are, and I hope some of you can help this newbie out, does it damage the 5 solenoids when you change out you tranny fluid? Where are the solenoids, and should they be replaced when you change your fluids? While looking at the electrical end, btw mine is producing about 13v, I did notice under the cover for the fuse box in the engine compartment that I am missing two fuses. They are the shift up 1 and the shift up res I believe. Are these supposed to be gone? Or did the previous owner take them out to cover up a problem or make it better for wheelin? Remember I am a newbie so no laughing! Thank you all so much for all of the info you put into this forum. You guys all help out naïve newbies like me be able to make better decisions about our vehicles and what to do with them. Thanks again.
 
#21 ·
Changing the transmission fluid would not damage the solenoids, but it is possible to damage the wiring to the shift solenoids when changing the filter. Selecting gear 2 or 3 when stationary will not permit a 2nd or 3rd gear start, the TCM will always select 1st gear unless Winter Mode is activated with D selected. For the transmission to upshift from 1st into 2nd the Shift A (1-2/3-4) solenoid has to energize. In order it select Winter Mode or 3rd gear the Shift A solenoid has to energize. Accordingly, it appears you an issue involving the Shift A solenoid. It could be defective or the wire to control the solenoid is open. The shift solenoids are accessed by removing the large transmission pan. The solenoid with the blue connector is Shift B (2-3), the one below it is Shift A (1-2/3-4) and the one with the brown connector is the PWM band solenoid. The filter covers the wiring when installed.
Corrected version
 

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#22 ·
Thank you very much for your response. So you think that maybe this solenoid has been damaged or just gone bad possibly? What about the missing fuses, and the fact that my truck will not go into winter mode? Again I am new to the trooper world and not sure whats the norm. If I do decide that the solenoid is the culprit, would it be a good idea to replace all of them at the same time, or should I just start with the one that seems to be giving me the problem? Thanks again for all your help.
 
#23 ·
I made an error in my post and corrected it, you have a possible Shift A solenoid problem as opposed to a Shift B solenoid. A replacement Shift A goes for around $30 on ebay. I personally would not change any other solenoids. The missing fuses are probably not causing the shift problem, what are fuses labled?
 
#25 ·
I don't have a 97 Trooper schematic so I can't tell what those fuses are for but it sounds like they could be for a manual transmission shift indicator lamp. In any case, both the shift solenoids and the band solenoid share a common +12 Vdc source provided by the TCM and there is no indication that Shift B or the band solenoid are not working so they must be receiving power.
 
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