This January I changed the tranny fluid and filter but never drained the torque converter. When I replaced the fluid, I used one qt. of Lucas tranny fluid and topped it off with regular Dexron III. A few days after I changed the fluid I noticed that sometimes it wouldn't shift at WOT and the shifts seemed softer. So I checked the fluid and it was about a 1/2 qt. low. I filled it up and the slipping problem went away, but the soft shifting still persisted. Then a couple of wks. ago I noticed that it started not wanting to shift at WOT again. When I noticed the problem again I immediately checked the fluid and it was fine. I have a Trans. Temp gauge in my car and noticed that the problem on happens after the Transmission warms up. If I go to WOT when it is cold the car shifts fine.

Before I changed the fluid and filter the car shifted nice and firm. Most of the time it'd even chirp the tires from the 1-2 shift. Also the fluid looked fine and nothing was unusual. I'm figuring that it's just time for a rebuild, but I wanted to make sure that there isn't something simple that I could be missing first. Thanks for any ideas or suggestions.

 

Could support my friends dad's theory of After a certain point you need the sludge in the trans to keep things together. He wouldnt change the fluid after 70,000 miles unless something wasnt working right. He really said i told you so when i had my 88' caprice got the fluid changed and suddenly a trans that never missed a beat started to act up. Just a thought

 

Yeah, you're the second person that has told me this. Actually, that was the reason why I didn't drain the torque converter when I changed the fluid in the pan and replaced the filter. From the way I understood it. All of the old shavings from normal wear and what not help the plates in there to mesh right. That would explain why it shifts correctlly when it's cold. Because the fluid in there is still cold and fairly thick.

 

It's just a theory that sludge helps, and a poor one at that. In the last 27 years of tearing down transmissions, I have not seen sludge in any in over 12 years. First, when you changed the fluid was there any black soot (clutch or band material) in the bottom of the pan? It will be a very fine powder, and will cover the bottom of the pan lightly. I am not familiar with Lucas tranny fluid, but I would say that it changed the holding power capabilites of the clutches and band. I would do a complete change of the fluid (no additives this time) to an AC Delco or Mobil (non-synthetic) type Dexron III fluid. Let me know?

 

I was hoping you were going to see this post and give me some insight. Anyway, yes there were some fine shavings in the bottom of the pan. But nothing that looked abnormal. Just the fine powdery shavings like you mentioned. I'm guessing thats just normal wear and tear, right? The only reason that I used the Lucas was because everyone talks so highly of their products. I'll do a complete change here in the next couple of days. I've also heard that our transmissions don't like the synthetics. Is this true? Thanks for your help. It is very appreciated.

 

Synthetics are fine. You said there were some fine shavings in the bottom of the pan, is this away from the magnet?, or is it covering the complete bottom of the pan?, and is it black in color?

 

My tranny has also started to do this. Firm shifts before it warms up but after that it softens up worse than stock. Also having the slipping and no shift at WOT. Happened after a filter and fluid change. I'm pulling the pan out tomorrow to take a look. I'll more than likely drain the convertor also. I'd just like to know if this is a fluid problem or the clutches are going out.

 

If I recall, the shavings weren't just at the magnet and I don't remember them being black either. What does it mean if they weren't just at the magnet? I'm guessing it's not good since the shavings weren't metal. When I did the change, I did it at my Dads buddies house so I could use his lift and he's a certified mechanic. When I dropped the pan he said that everything looked normal, except that it was in definate need of a fluid change. I just don't understand why it would operate fine before the change and act up afterwards. Transmissions are one thing I need to sharpen up on though.

 

my friend noticed some similar problems with his tranny (700 r4) after a fluid and filter change. it was not shifting as hard either. his just took some time to get back to normal. he put some more miles on it and it seemed to get a little better. i don't know if you have any cables or anything on your tranny but in my friends third gen, the kick down cable needed adjusted. i would just change the fluid and put the brand you want in and get some miles on it. also, make sure when your checking the level your doing it properly. i think my friends third gen had to be warm and running when you ckeck the fluid level. sorry i don't know much about 4th gen autos, i drive a 6-speed. good luck and let us know if it gets better.

 

Thanks for the info man. I've checked the fluid numerous times with the car running and have also had someone else check it. Just to be safe. The level was fine. I'm figuring it's time for a rebuild. I just wanted to make sure I wasn't over looking the obvious, before I shelled out 900 bucks for it to be rebuilt. Thanks for all of the help guys.

Let me know about them shavings though ProBuilt. Thanks

 

Pro Built. If you have AIM give me a hollar. I'd like to talk to you about your trannys.
Thanks, Rich

My AIM screen name is HOOZNXT1.

 

The black powder I was referring to is clutch or band material, which is not magnetic. I am not sure why this seems to happen, when you do a fluid change it starts to cause problems. It might possibly be that the old fluid might have been thicker (in terms of viscosity), or that the new oil is much more slippery than the old fluid. If this is the case, it reminds me of what you use to do to prolong transmission life (so you could save up for a rebuild) back in the 1970's & early 1980's (TH350's & TH400's were common) was to drain a two quarts of transmission fluid, then add a couple of quarts of motor oil (detergent) 30 or 40 weight. This would work some of the time, as it would keep the fluid on the thick side when hot, and you were only out a few dollars. I have not tried this in years, and at best it is probably only a temporary fix, but a temporary fix is better than none at all. One side effect is that (the fluid being on the thick side) when cold it might not shift correctly, until warmed up (3-5 miles).

 

ProBuilt. I sent you a PM.

Thanks a ton for your help and input.