Transmission issue?

LCL-Dead

LCL-Dead

It broke.. ..again
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Havelock, NC
I did a couple of searches and looked through recommended/similar threads when I started typing this up, couldn't find an existing thread that I thought lined up with my issue.

06 Rubicon, automatic trans, when the jeep is warming up it doesn't want to shift unless I fiddle with the gas pedal. 1st-2nd it hangs/hesitates and literally jerks the vehicle a bit when it shifts and rolling around between 35-45mph it hangs in the lower gear unless I fiddle with the gas a bit.

I noticed in a lot of threads that people were checking over the TPS and a few other bits and pieces. With this cropping up I'm going to go have the fluids flushed and filter changed. What else should I look into?
 
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How many miles is on your Jeep ?

The 42RLE is a quirky transmission, shift points are unpredictable sometimes but mine has been trouble free.
I'd first check your fluid level and do so with a white paper towel so you can see the color, it should be bright red.
 
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113k on the odometer. When I brought it home the original owner noted that it would probably be a good idea to get the trans and coolant systems flushed. I guess it's that time.
 
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I don't know if 'flushing' a high mileage transmission is a good idea. Read and was told by two different people who've had poor results doing the same w a high mile trans.

Anyone else care to chime in or contribute whether this is truth or urban myth?


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Two suggestions: FIrst, check the ATF level, it could just be low. The engine MUST be running and warmed up during the ATF check, your transmission can be in Park or Neutral for the level check. You'll get an inaccurate level check from an automatic transmission if the engine isn't running while you check its ATF level.

Second, if the transmission level is up where it should be, your problem could be a sticking check valve located in the transmission above the transmission pan. Its job is to keep the torque converter and transmission full of ATF so nothing slips when you first put it in gear. If that check valve leaks, there won't be enough ATF inside the torque converter and transmission for it to work as soon as you shift into Reverse or Drive. That delay you're encountering is caused by how long it takes the pump inside the transmission to refill everything after it has leaked down through the bad check valve.

The leaking check valve would be pretty well confirmed if it takes a few seconds to 'go' after shifting into Reverse or Drive after sitting over night or at least several hours.

And I guess it could also be a bad Throttle Position Sensor too.

fourpointzero said:
I don't know if 'flushing' a high mileage transmission is a good idea. Read and was told by two different people who've had poor results doing the same w a high mile trans.

Anyone else care to chime in or contribute whether this is truth or urban myth?
Click to expand...
Urban myth. If it fails after the ATF is changed/flushed, it was about to fail anyway. Flushing the transmission with the correct ATF is always a good idea when it's time.
 
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I serviced mine this past weekend and it shifts real smooth now.
I used a pump to pull the fluid from the dipstick tube and then refilled it with the same amount of fluid removed.
I plan on doing this again in 1500 miles and then drop the pan and replace the filter.
Be sure to use the correct fluid, ATF+4 only.

Let us know how the flush improves your tranny.
 
Jerry Bransford said:
Two suggestions: FIrst, check the ATF level, it could just be low. The engine MUST be running and warmed up during the ATF check, your transmission can be in Park or Neutral for the level check. You'll get an inaccurate level check from an automatic transmission if the engine isn't running while you check its ATF level.

Second, if the transmission level is up where it should be, your problem could be a sticking check valve located in the transmission above the transmission pan. Its job is to keep the torque converter and transmission full of ATF so nothing slips when you first put it in gear. If that check valve leaks, there won't be enough ATF inside the torque converter and transmission for it to work as soon as you shift into Reverse or Drive. That delay you're encountering is caused by how long it takes the pump inside the transmission to refill everything after it has leaked down through the bad check valve.

The leaking check valve would be pretty well confirmed if it takes a few seconds to 'go' after shifting into Reverse or Drive after sitting over night or at least several hours.

And I guess it could also be a bad Throttle Position Sensor too.

Urban myth. If it fails after the ATF is changed/flushed, it was about to fail anyway. Flushing the transmission with the correct ATF is always a good idea when it's time.
Click to expand...

Thanks for chiming in! I don't have a hesitation when shifting into drive/reverse when I first turn it on in the morning and, once the engine is warmed up, the shifting issue goes away. Hell, this morning it did it once, albeit less pronounced, when I first left the house and it was shifting from 1st to 2nd and then it didn't do it again and actually cruised at 1400rpm @ 45mph rather than almost 2100rpm.

I checked fluid levels yesterday after going for a quick drive to warm it up and it wasn't low. I'm going to give the local NTB a call and see if they do a transmission flush/fluid change and for how much, then get it scheduled.

It's bad enough I still need to drop almost $500 on new control arms and the labor to have the mounts fixed.. I don't think I can afford to rebuild/troubleshoot the transmission for too long.

DickD1911 said:
I serviced mine this past weekend and it shifts real smooth now.
I used a pump to pull the fluid from the dipstick tube and then refilled it with the same amount of fluid removed.
I plan on doing this again in 1500 miles and then drop the pan and replace the filter.
Be sure to use the correct fluid, ATF+4 only.

Let us know how the flush improves your tranny.
Click to expand...

I'd do it myself if our local hobby shop had the equipment. I'm going to check with them one more time since I'm working off of an assumption from another base that didn't have the capability to do the flush.
 
All you need to flush your transmission is a large enough bucket (or two), 9 quarts of ATF+4, 3-4' of 3/8 I.D. rubber hose, and a small plastic funnel that will fit into the transmission's dipstick tube. No "machine" is needed.

Disconnect the driver's side transmission cooler hose and connect the rubber hose to that port on the transmission. That is the output side of the cooler inside the radiator. There are various types of fittings used there, you can figure out how to connect the hose to it. Pull the transmission's dipstick out and place the small funnel into the dipstick opening. Don't confuse the transmission's dipstick for the engine's dipstick.

Place the other end of the hose into the bucket and start the engine. ATF will start flowing out of the hose connected to the driver's side port at the bottom of the radiator. At the same rate the ATF is being pumped into the bucket, add fresh ATF+4 (nothing else!!) from the dipstick tube via the funnel. Once you've got bright clear red ATF flowing into the bucket, it is essentially flushed if you're within a quart of running out of ATF. Stop the engine. Remove the hose from the cooler port on the radiator and reconnect the normal cooler hose.

Start the engine and bring the ATF level up to full with the remaining fresh ATF+4 not poured in through the dipstick tube.

Your transmission is now flushed.

Regarding the transmission filter inside the pan, you need to drop the pan to get to it so it can be replaced. Here's a writeup on replacing it I found... https://project-jk.com/jeep-jk-write-ups/jeep-jk-wrangler-42rle-automatic-transmission-service
 
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As I've never flushed a transmission myself, and I do appreciate the quick notes on doing it, I took it to a shop to have it done. :p

However, it's still hesitating shifting. I know I said it had no issues coming down but I threw it into 4 low and engaged my lockers just to mess around a bit and noticed it was hard shifting from 2nd down to 1st as well when I would put on the brakes.

The only change since the flush (I flushed it yesterday afternoon) is that it seems to take a bit less time warming up to the point where it begins shifting at the right RPMs again. All week I could drive to the gas station on base (3 miles) and it wouldn't shift into the next higher gear, leaving me at 1900-2100rpm while cruising at 45 mph. Today I was halfway to the gas station and watched it drop into it's normal cruise range of about 1300rpm after only a mile or so.

Not sure what to do here. This all just kind of suddenly started this past weekend.

Edit: Transmission fluid looked like grape juice coming out. It definitely needed the flush.
 
I'm curios to know if the guys with the transmissions the puked at lower miles were running taller tires without re- gearing. That would be a factor.
 
I'm giving it a couple of days to see if it sorts itself out. I've got a 52 mile drive on Saturday and ill be taking the jeep just to let it stretch its legs a little.

If it doesn't stop after that then ill look into some rebuild kits and take it to a shop to get properly diagnosed.
 
Andy5150 said:
I'm curios to know if the guys with the transmissions the puked at lower miles were running taller tires without re- gearing. That would be a factor.
Click to expand...

I'm sure that could be a factor.
I'm not crazy about how quick my 42RLE wants to shift into a higher gear but its been trouble free and shifts very smoothly .
My brother has 168K on his so with proper care it's possible that this tranny will last the life of the vehicle, like you'd expect a tranny should.
 
Old thread but just wanted to bring this up. My 42RLE has 230k on it right now with no rebuild. Last time it was flushed was maybe 6 years ago. I was 12 when that happened lol. But I have been experiencing this shudder in the cold mornings, when it shifts 1st to 2nd, the jeep shakes and kind of sends me forwards and then backwards abruptly. This isn't something that occurs often but just something I noticed that has happened on a few cold mornings. I plan on doing a full ATF flush in the very near future but I am currently replacing my rear passenger axle seal. Could this mean my tranny is on the way out or just in need of a new fluids(or both)? I saw @Chris mentioned in another thread that a good way of seeing if your 42RLE is on it's way out is flooring it and seeing if it shifts gears smoothly. Definitely gonna try that out tomorrow.
 
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Hard 1 to 2 shifts is a common problem with the 42rle. It's usually the PCM, which can be tested by resetting it and seeing if it goes away for awhile.
A shudder sounds like the torque converter is going bad. Definitely try a fluid flush first.
 
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Haaris Khan said:
Old thread but just wanted to bring this up. My 42RLE has 230k on it right now with no rebuild. Last time it was flushed was maybe 6 years ago. I was 12 when that happened lol. But I have been experiencing this shudder in the cold mornings, when it shifts 1st to 2nd, the jeep shakes and kind of sends me forwards and then backwards abruptly. This isn't something that occurs often but just something I noticed that has happened on a few cold mornings. I plan on doing a full ATF flush in the very near future but I am currently replacing my rear passenger axle seal. Could this mean my tranny is on the way out or just in need of a new fluids(or both)? I saw @Chris mentioned in another thread that a good way of seeing if your 42RLE is on it's way out is flooring it and seeing if it shifts gears smoothly. Definitely gonna try that out tomorrow.
Click to expand...
The hard 1-2 shift after sitting overnight is a classic indicator that the transmission control circuits inside the PCM have failed.

Many of us with '05-'06 TJs/LJs got our PCMs from @Wranglerfix https://wranglerfix.com
 
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