95 Jerky Trans

[Yeki]

Hello All!

I recently purchased a 95 4runner. Over all, it runs pretty good. It has 140,000 miles on it and the 3.0. The problem I am having is that sometimes after stopping at an intersection, when I hit the gas to take off, it feels like the trans is jerking. If I ease of the gas, it will coax into gear and go, sometimes with a hard "bam". All other gears shift nicely and a load doesn't change the characteristics.

Any ideas?

Thanks folks!

 

[SV_Dude]

Automatic transmissions are very temper mental when they don't have good fluid. I would do a fluid and filter change and see if that changes anything.

If that doesn't fix it and I had to make a mechanical guess, I would guess that maybe the torque converter is starting to go out?

 

[Yeki]

Thanks for the input SV Dude! Would you suggest a complete flush or just a change?

 

[SV_Dude]

The only way to completely get all the old nasty fluid out is with a complete flush. The torque converter holds a lot of fluid too so I would definitely recommend a flush. Depending on what a shop charges, you could do your own flush... kind of. Drain the fluid and replace the filter, refill fluid. Drive on it for 10-15 minutes and drain fluid and replace filter again. It's a make shift drain and flush but that is what we do on our helicopters. A bit of a different animal but the principal is the same.

 

[Yeki]

Thanks again SV Dude.
As an aside, the problem is definitely intermittent. It did it quite a bit on the way home last night. It didn't do it at all on the way in this morning. Also, for the first time, it felt faintly jerky at highway speeds (55-60) yesterday, whenever I hit the gas to speed up.

 

[SV_Dude]

It could be the torque converter but it could be other things too. I'm not very smart on auto transmissions but I do know that they will not cooperate when they have old and broken down fluids.

Maybe someone with more experience with an auto tranny could chime in...?

 

[ozzyleven]

Yeki, I would skip the flush personally, since you don't know its history (maybe you do). I've heard way too many horror stories about screwing up autos that way.

When I got mine 94, the AT fluid was almost black and it had a really hard shift between first and second. What I did was drain and drop the pan the first time. Clean it out really good (I used break cleaner to un-gunk the pan and let it dry), there magnets in there that will let you know if things are really chewed up. Mine were coated with shavings and there was a thick layer of grey-black sludge (RTV gone wrong?) on the bottom of the pan. I did the filter while I was in there. For three more oil changes after the first drain, I did a drain and fill. After all that, I have AT fluid that actually stays red for more than one oil change and the hard shift is barely noticeable now. So it definitely helped to get all the fluid cleaned up.

After you get the fluid taken care of, see if the problem persists. If it truly is an intermittent problem, my bets would be on a sensor or solenoid. Also, is the vehicle all the way to operating temp? Even when mine is, if I immediately get on the interstate (half mile from house) its not warmed. I had a freak out when I first got mine thinking I had just bought a toasted transmission, but turns out the trans needs to get to a certain temp before it will shift into the higher gear nicely. The RPMs would go way up around 55 mph and then it would seem like it was jerking and finally give a hard kick when it went into 5th.

 

[DC runner]

Yea. Do what the man above recommends. I hate posts like this because it could mean bad things. You literally have to be ginger on those old AT transmissions.

The horrid thing about a flush on old transmissions is it has a tendency to f stuff up. All those bits ans shavings get pushed around and clog things. Better to be easy and do several simple drain and fills.

 

[rustbucket]

I would try the above. I recently bought a new(used) trans for my 89, The only gear I had was reverse and park, didn't matter if it was in drive 1or 2 I only got reverse.......so I deemed mine dead andits been parked unmoved or started for over a year now. Sounds like yours can be saved.

Not looking forward to droping mine and installing the replacement, getting the replacement out of the oter truck wasnt fun an I dd it for free lol.

Good luck.

 

[Yeki]

Thanks for the advice guys! It makes sense to me. I'll try it!