TH350 slipping??

[rockstarnrg4me]

I've tried searching... but nothing came up so I'm creating a post to get a quick answer. OK so I got my trans rebuilt late last year and recently when its cold (first start of the day) and I put it into gear, whether it be REVERSE or Drive it slips like I'm driving a manual. I took it back to him and he said it needed some adjustments, so I drove it home and the next morning I started it and still the same thing... Its been there for a couple of days and he says it needs one more day. I'm just curious if you guys might know wtf is going on with it?? Side notes, it only does it really bad when first engaging and slowly goes away once it starts warming up. I also feel its really sluggish once warmed up. IDK... that just might be me thinking its sluggish lol. As for the truck its a 350ci/ TH350 on 37's with 4:10 ratios. Any input on this would be greatly appreciated.

Thanks,
Brett


and just for the heck of it a few pics of it

 

[lectric80]

I rebuilt my T350 last year for exactly that reason, but never found a for sure reason it would do it. It doesn't do it since I rebuilt it, but since I am no expert I couldn't tell you what was causing it.

 

[owenst7]

I would say pump, but it's only doing it in reverse?

Reverse is operated by applying a big piston in the very very back of the case...it gets pushed forward by fluid and clamps a set of clutches. If it is slipping, it's not getting enough fluid pressure to it (does it behave differently if you rev it up at all? this would increase flow from the pump).

Working backwards in my head, possibilities are:
frictions themselves
reverse piston seal
hydraulic circuit messed up going to the piston (like clogged or the valve body gasket)
valve body
pump

edit: just reread your post and noticed I'm pretty out of it. I'll try to get back to you when it's not 2 am haha

How are the shifts from 2-3?

 

[lectric80]

I would say pump, but it's only doing it in reverse?

Reverse is operated by applying a big piston in the very very back of the case...it gets pushed forward by fluid and clamps a set of clutches. If it is slipping, it's not getting enough fluid pressure to it (does it behave differently if you rev it up at all? this would increase flow from the pump).

Working backwards in my head, possibilities are:
frictions themselves
reverse piston seal
hydraulic circuit messed up going to the piston (like clogged or the valve body gasket)
valve body
pump

edit: just reread your post and noticed I'm pretty out of it. I'll try to get back to you when it's not 2 am haha

How are the shifts from 2-3?

You may be right, if I remember correctly, since I don't have my book here, that is the low/reverse piston, so it would control both directions. On mine the seals were worn and stiff, replaced them as part of the rebuild, in spite of needing to create a tool to remove the snap ring and spring pack.

Edit: If it is that piston, I am not aware of any adjustments that can be made from outside the case. The entire trans has to be torn down, and that is the last part to be removed. It is possible they either didn't rebuild it, or they damaged the seals when they were re-assembling it.

 

[Greg Ducato]

Sounds like a converter drainback issue, when you start it and drop it into gear you are having to wait for the converter to fill. There are valves available that can be put into the return cooler line to prevent this. The problem will not go away if the pump is badly worn or there is a lot of stator bushing wear.

 

[rockstarnrg4me]

Hmmm okay... Well if I got it rebuilt should that piston have been replaced? The trans guy said even my casing was bad, so he replaced that too! (and another 100 bux for it) all in all the rebuild was 800, is that a fair price for a rebuild and would that or should that have included all new Clutches and whatever else?( I have no idea about transmissions sorry) I am just getting frustrated cause I've had to take it back to him a couple of times... it has a 1yr warranty which is awesome and he has never had a problem with me taking it back to him... but I just really want this fixed as I don't want to be out on a trail and it goes out on me.

I would say pump, but it's only doing it in reverse?

Reverse is operated by applying a big piston in the very very back of the case...it gets pushed forward by fluid and clamps a set of clutches. If it is slipping, it's not getting enough fluid pressure to it (does it behave differently if you rev it up at all? this would increase flow from the pump).

Working backwards in my head, possibilities are:
frictions themselves
reverse piston seal
hydraulic circuit messed up going to the piston (like clogged or the valve body gasket)
valve body
pump

edit: just reread your post and noticed I'm pretty out of it. I'll try to get back to you when it's not 2 am haha

How are the shifts from 2-3?

To answer the very last question about shifts from 2-3 they are ok.. but if I were to step on it, it downshifts like it can't make up its mind, then finally does.


I thank you all in advance for this input So, in the end do you guys think this problem could be solved but "adjustments" made outside the trans? Just for clarification... It slips through out the shifter column at first start of the morning... I can put it in 1, 2, Drive and Reverse and it slips bad! I step on it and it slowly engages. As soon as maybe as was previously mentioned the Pump finally gets fluid... and then starts doin its job.

Brett

 

[rockstarnrg4me]

Also, I had the column replaced by another shop and the shifter linkage?? was wearing out so it had a hard time finding and engaging in gears. He said he tightened it till he could order the part, but he said he tightened it but it should be replaced soon. The "tightening" helped a great deal. Now for another question... is any of THIS related to my morning starting issues?? Cause at the same time of my morning start before I got the thing tightened 1 I couldn't find a damn gear. The #2 came and that was the slipping. So I figured I'd take it to where I got the column along with a few other things replaced and see if he could see anything while going through and tightening stuff up. He found that linkage thing needed replacing and also mentioned my trans was slipping pretty bad. Could any of this be related?? Or are they just separate issues?

Thanks again in advance.

Brett

 

[Greg Ducato]

Those problems are probably not related

 

[rockstarnrg4me]

Those problems are probably not related

Sweet. Good to know.

Ok so I went to go pick it up a short while ago and he said he tried it yesterday morning and this morning and it didn't do it. Fair enough I said, he said go try it right now and it shouldn't do it. Sure enough, I went to go try it and it did it immediately. He tested it himself and says he's gotta drop the trans on Monday, he thinks it may be the Forward Drum?? Any insight on this?

Thanks again,
Brett

 

[y5mgisi]

My bet is he knows exactly what is wrong. And now that he has agreed to drop the trans, im sure he will fix it. Forward drum is a part in the trans. I bet he thinks he ****ed up a seal in that drum.

 

[rockstarnrg4me]

He did mention something about maybe being a seal... Alright well we'll see on Tuesday. Thanks mil guys.

Brett