Transmission slipping

My daughters 2000 4WD Rodeo LS Automatic slips occasionally, usually when starting out on an uphill / slope. Otherwise I don't feel much problem, maybe a tad sloppy 1st to 2nd upshift, but that's very minor if not my imagination. The ATF and filter have been changed at least twice at 103,000 miles. Last change showed some browning of the fluid, but it didn't seem or smell burnt. If I accelerate pretty hard but keep it from dropping into passing gear, it also seems to be OK, just that uphill slope thing.

I'm guessing fluid level is the first thing to look at, and I have a pint of Transx additive I thought I might try. Any thoughts?

Thanks!

your range selector may be dirty (common) see the faq's for more information.

Found and printed the FAQ about the range selector. Other posts I have seen about the selector seem to deal more with shift problems than what I think I might be dealing with--a shudder. On an uphill slope from a standing start we get a pretty good shudder. I plan to check the ATF level and look at the range selector. Any other thoughts? Thanks

check out the faq's for driveline thump or clunk.

This doesn't sound like a descripition of our problem. Ours isn't a single thump or clunk, but multiples- a shudder or judder as the transmission slips for a few seconds. We get forward movement but it's bumpy/jerky until it settles in. Thanks

Double check your ATF level, sounds low.

Just noticed my little overdrive pan gasket has started weeping again, which I don't understand, both these gaskets were replaced last year. Gonna double check my own level this morning. Mine's not slipping however, thank goodness.

Not quite sure what it feels like on this tranny when it does start to slip, but a shudder, etc doesn't sound right.

Is your daughter a harsh driver?

She's a good driver and isn't pushing it. I test drove it for about 20 minutes and experienced it. The shudder/judder is pronounced, but brief. One thing making me look at the ATF level is that I didn't experience it except on the uphill slope. We changed about 4-5 qts. of the ATF a month or more ago and it's gotten worse/more frequent. I told my son-in-law to get 10 qts of some brand name High Mileage ATF and we'll take another shot at this.

Ok. I've had this happen before. At about 55k, with 25k on the fluid, at about 53-55mph going uphill the tranny would jump back and forth gears. I took it in and they told me my intake manifold gasket was leaking and was causing the issue. It sorta fixed it. So since it was still happening, I decided to have the tranny flushed, thinking maybe the fluid was dirty (or most likely a little low).

They flushed it and the issue has not come back after 31k (which reminds me I need to go to the dealer and have them drop the tranny pan and replace the filter this time 86k on the ticker).

My guess is that your fluid is a bit low.

We'll be changing the ATF soon, but not before checking the fluid level. I had changed the filter about 30K ago, that being the second time the filter had been changed. Will let you know what happens. Thanks for the help.

Yep, double check your level.

Mine turned out to be 1/2 qt low, thank goodness I checked it when I did.

Changed the ATF again and went to great lengths to be sure it was topped-off when running, etc. No improvement. Fluid was brown, not black, although I am a bit suspicious of the color given it's had several fluid changes (about 4 -4 1/2 qts. each time) in the last few weeks. I expected clearer & redder. I put a couple drops on a white paper towel and it wicked out even, brown, no grit apparent, no separation of fluid, etc. Added a transmission additive called TransX, since I had some and we were at it. No improvement.

Removed, cleaned and replaced the range selector (very dirty and one adjustment mount bolt was loose allowing it some movement) No improvement. Tried a couple positions of adjustment but no change.

Changed the rear differential lube and added an anti-slip additive; again no change.

This thing shudders, judders, slips and misbehaves seemingly only when you accelerate hard from a standing stop, up a hill, etc., when there is some pretty good stress on the low gear. It's fairly brief, but very noticable-subtle it ain't. All other shifts & gears are smooth; normal to easy start from a stop, or from slow speed there's seldom any shudder.

I am beginging to suspect a weak motor or transmission mount-maybe pulling the selector in/out of gear. Looked at the engine movement when stopped, brakes on, in gear but nothing suggested major engine movement.

The tranny will do strange this with a weak electrical system. Weak battery, or dirty ground points

I gotta agree with you about something going on in there due to the fluid already being discolored. My last partial fluid swap, at 15K, showed very good looking fluid. It wasn't quite the cherry red of the new fluid, but it was pretty clean. Is there any chance this truck is running hot?

Agreed, condition of fluid doesn't sound right, should be clear pink with that many atf fluid swaps.

Was hoping for the best for you, as that tranny's not that old.

But, doesn't sound good.

Consensus from a shop I completely trust and the transmission shop that first shop uses is the sprague is weak or worn and it's time to replace the transmission.

Now the question becomes how to go about this-buy used, buy rebuilt, call the dealer for a re-man, etc. Anyone got suggestions where a decent used unit could be had, or where a reliable rebuilt could be obtained?

The tranny shop I took it to said parts were getting very hard to find for these, can you steer me to a good parts place, and maybe we'll have him rebuild it. He's to get back to me.

Thanks

Depending on where you are located, St Charles Isuzu is out on the west coast area (I think they're in Missouri?) and there is a good dealer is Charlotte, NC - Folger Auto 1-704-536-9635. I have ordered OEM stuff for my 2001 Passport on a couple occasions from Folgers and they have gotten me the exact parts I needed. I have heard a lot of good about St. Charles, and I think you can Google thie name to find the contact info.

Good luck!

Mark

My 94 has been doing this for over six years.

out of curiousity, what brand of ATF fluid are you using?

There ARE some ATF fluids that will make this tranny feel weird.

I stopped using the Maxlife ATF cause I didn't like the rough way it would make the 2nd shift.

I went back to Castrol Import ATF, all is good.

It's all Dexron III or the more recent upgrade. We have used a couple different brands, the Autozone private label and the last flush & fill was Castrol. The last fill before the trouble started was about 30K and two years ago. I changed the filter and had some synthetic ATF that went in then, but it worked fine until about 30-60 days ago.