Odd Transmission Behavior - Harsh Shifting? 32RH

[Beachhead]

2000 4.0, 32RH Auto.

Recently took the transfer case out of my Jeep and rebuilt/replaced parts of it. It had a TeraLow in there and I put a normal 231 back.
My transfer case issue was solved, but first time driving it I noticed some odd behavior from the transmission.

When putting it into drive, i'll give it a little gas and it won't go anywhere, then suddenly it will lurch forward and go. This has happened a few times where i'll go from reverse to drive, park to drive, or neutral to drive. (sort of the same feeling if you release the clutch too hard on a manual, but not as jolting)

Then I've noticed some harsh downshifting from 3rd to 2nd getting on the onramp, intermittent, and once from sitting at a stop sign while in drive, harsh engagement when pushing on the throttle.

Fluid levels are good, as I checked (while hot in neutral) after putting the transfer case back in, and filled accordingly.

The Jeep did sit for almost a year while I rebuilt the transfer case, so the first time I drove it I thought maybe it was just a little sticky from sitting, but i've been trying to drive it often and it's still doing it intermittently, most commonly after it's been parked, after i'm driving around for awhile it seems to go away.

All procedures and precautions were taken when doing the t-case work, transmission was supported, everything went back together just fine.
I replaced the transmission filter and fluid just last year so it's fresh.

Any ideas on if I caused something and if so what? We were very careful not to pinch any cables or mess with anything else other than the transfer case lever.

Thanks.

 

[primetime4]

This sounds similar to an issue I had with my Jeep after letting it park for a few hours. I tracked the cause down to fluid draining out of the torque converter when parked sometimes known as "morning sickness". There is a drain back valve in one of the cooling lines that was no longer doing its job and replacing the lines successfully fixed it. You can try letting it sit in neutral a bit before changing gears until the converter fills back up to confirm if this might be your problem.

 

[Beachhead]

This sounds similar to an issue I had with my Jeep after letting it park for a few hours. I tracked the cause down to fluid draining out of the torque converter when parked sometimes known as "morning sickness". There is a drain back valve in one of the cooling lines that was no longer doing its job and replacing the lines successfully fixed it. You can try letting it sit in neutral a bit before changing gears until the converter fills back up to confirm if this might be your problem.

So i've been shifting into neutral before going into drive and the issue seems to have stopped. It does occasionally sound like it wants to stall when I shift into drive, but it hasn't been stuck like it did before. Sounds like i've got the drain back valve issue, and replacing it should fix this issue?

 

[Jerry Bransford]

Sounds like it's low on ATF. Check its level only (!) while the engine is running and the transmission in Neutral. It needs to be all the way up to the full mark. If it's low insert a small funnel into the dipstick tube and add enough ATF+4 (only!) to bring it to the full mark. It's better for an automatic transmission to be slightly overfilled than slightly underfilled.

Also the TV/kick down cable may be adjusted too tightly which will cause harsh higher rpm shifting. It should be adjusted so it is taut with no slack but not actually pulling on the TV valve on the transmission when not stepping on the gas pedal.

 

[Beachhead]

Sounds like it's low on ATF. Check its level only (!) while the engine is running and the transmission in Neutral. It needs to be all the way up to the full mark. If it's low insert a small funnel into the dipstick tube and add enough ATF+4 (only!) to bring it to the full mark. It's better for an automatic transmission to be slightly overfilled than slightly underfilled.

Also the TV/kick down cable may be adjusted too tightly which will cause harsh higher rpm shifting. It should be adjusted so it is taut with no slack but not actually pulling on the TV valve on the transmission when not stepping on the gas pedal.

ATF should be good, I just filled it when I replaced the transfer case, but it was inbetween the full and fill marks so i'll double check to make sure.
My transfer case rebuild has developed a leak now, I think it's the shift lever which I didn't replace the o-ring on as I was tired of fighting with it, so i'll be taking the skid plate down this weekend to diagnose and hopefully fix that and i'll check that cable as well. Thanks Jerry.

 

[Jerry Bransford]

ATF should be good, I just filled it when I replaced the transfer case, but it was inbetween the full and fill marks so i'll double check to make sure.

Make sure the transmission is in Neutral (not Park!) and that the engine is running while checking its ATF level. If the transmission is in Park or the engine is not running while checking the ATF level the dipstick will erroneously show significantly more ATF is present than there really is.

Being all the way to the full mark or slightly over that is much better than being between fill and full as it can suck air when slightly low, especially when on a slope.

 

[rodsstang]

2000 4.0, 32RH Auto.

Recently took the transfer case out of my Jeep and rebuilt/replaced parts of it. It had a TeraLow in there and I put a normal 231 back.
My transfer case issue was solved, but first time driving it I noticed some odd behavior from the transmission.

When putting it into drive, i'll give it a little gas and it won't go anywhere, then suddenly it will lurch forward and go. This has happened a few times where i'll go from reverse to drive, park to drive, or neutral to drive. (sort of the same feeling if you release the clutch too hard on a manual, but not as jolting)

Then I've noticed some harsh downshifting from 3rd to 2nd getting on the onramp, intermittent, and once from sitting at a stop sign while in drive, harsh engagement when pushing on the throttle.

Fluid levels are good, as I checked (while hot in neutral) after putting the transfer case back in, and filled accordingly.

The Jeep did sit for almost a year while I rebuilt the transfer case, so the first time I drove it I thought maybe it was just a little sticky from sitting, but i've been trying to drive it often and it's still doing it intermittently, most commonly after it's been parked, after i'm driving around for awhile it seems to go away.

All procedures and precautions were taken when doing the t-case work, transmission was supported, everything went back together just fine.
I replaced the transmission filter and fluid just last year so it's fresh.

Any ideas on if I caused something and if so what? We were very careful not to pinch any cables or mess with anything else other than the transfer case lever.

Thanks.

Check the governor pressures for a sticking governor, it almost feels like the trans is starting off in second and then a downshift on takeoff. Which indicates a sticking governor. You may have picked up some dirt during the transfer case work.

 

[Beachhead]

Make sure the transmission is in Neutral (not Park!) and that the engine is running while checking its ATF level. If the transmission is in Park or the engine is not running while checking the ATF level the dipstick will erroneously show significantly more ATF is present than there really is.

Being all the way to the full mark or slightly over that is much better than being between fill and full as it can suck air when slightly low, especially when on a slope.

Wanted to report back on this topic. My transmission rear output seal was apparently bad, as I replaced it and i'm not getting a leak from the seam between the transfer case and transmission now. I also replaced the anti-drainback valve today.

After I took out the transfer case and replaced the transmission seal, I drove it before filling back up with fluid as I didn't want to overfill. Got the harsh shifting again after driving it up the road a ways. I filled it somewhere inbetween min-max on the dipstick after i got back home. Engine running in Neutral.

Today I replaced the anti-drainback valve, took it for a drive and that really seemed to fix that particular problem of it starting off weird, I didn't get any harsh shifting this time, but I did check the level when i got back anyway and it wasn't quite to the full mark, so i added more ATF, and it's still not at the full mark. I've put almost an entire quart of ATF down the tube now and the level doesn't seem to change much. Should I keep adding?

I didn't lose that much ATF when doing the repair work so it seems odd. I'm worried about the oil foaming over on me as it should have more than enough now but the levels still show it down near the min mark.

 

[Jerry Bransford]

Keep adding ATF+4 until it's all the way up to the full mark, An automatic transmission is not an engine that can be damaged by running too much engine oil. It's better for an automatic transmission to be slightly overfilled as most of us rock crawlers do than to be slightly underfilled. Mine is routinely overfilled by about 1/2 quart to keep it from sucking air on steep climbs.