Thread: TH350 no shift when cold?

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Originally posted by pat mccarthy
the hard part will be compressing the spring packs on the drums but you can make some thing up i have used 2 C lamps and on the front pump flip it and i use the case to line up the front pump haves .to bolt them up

Thanks Denny and Pat,

Already bought 2 C clamps at wal-mart at $0.97 each. Beats the heck out of a ram press huh?


Yeah, I was wondering how to line those up without the dowel pins that the manual speaks of, so thanks for the rebel intelligence Pat! Also found an article from hot rod mag. with picture showing the assembly turned upside down in the case to line it up.

Question: Had the tranny bottom side up on the bench removing the valve body; the manual shows there are supposed to be 4 check balls, but after removal of the valve body, I only found 1 in the #1 position shown. I was real careful not to misplace any or let them stick to the separation plate when removing it????

I do believe the trans had a shift kit installed previously. Do those kits eliminate any of the check balls????

yes they do. it has a lot to do with the shift kit it had in it. you need to find out what you had in it. or get a new one and start over i do not know how hard you want it to hit . watch the C clamps that you do not bend the spring pack retainer i had some steel i used for a backer. like a horse shoe to keep from bending the retainer

Originally posted by pat mccarthy
yes they do. it has a lot to do with the shift kit it had in it. you need to find out what you had in it. or get a new one and start over i do not know how hard you want it to hit . watch the C clamps that you do not bend the spring pack retainer i had some steel i used for a backer. like a horse shoe to keep from bending the retainer

Ok that sounds good.

Before trouble started, it used to shift mild at light throttle and bark 1st to 2nd and chirp 3rd on heavy throttle. This was fine with me but does it cause premature wear????

I need to investigate the shift kits more to know what they come with. Seems that the separator plate gaskets are tough to remove. Do the shift kits come with plates??? Are these gaskets supposed to be so tough to remove from the plate???

I hate being a rookie!!

Originally posted by s10streeter
Ok that sounds good.

Before trouble started, it used to shift mild at light throttle and bark 1st to 2nd and chirp 3rd on heavy throttle. This was fine with me but does it cause premature wear????

I need to investigate the shift kits more to know what they come with. Seems that the separator plate gaskets are tough to remove. Do the shift kits come with plates??? Are these gaskets supposed to be so tough to remove from the plate???

I hate being a rookie!!

i think there is two bolts and backer plate that have to come out below the valve body to get the plate off the plate between the valve body and trans case ??if they hit hard they will wear your neck out .on the street you do not need that .less you like it ??

A smooth shift would be nice. But, do I need a shift kit for performance? Do they increase the trannys torque or power capacity? Can I use stock configuration in the valve body? I only make about 310-315HP and 370ftlbs.

Your trans more than likely has a shift kit since there was only one checkball. To go with a stock configuration, you will need a new separator plate and possibly a second valve body. With a shift kit, the separator plate has had some holes enlarged the valve body might have had some springs changed.

Originally posted by s10streeter
A smooth shift would be nice. But, do I need a shift kit for performance? Do they increase the trannys torque or power capacity? Can I use stock configuration in the valve body? I only make about 310-315HP and 370ftlbs.

stock trans are made to slip some in stock form. so when you put a shift kit in it this will make it hit hard and takes some of the slip out so it will take more hp. the kit will have steps in them for rv . street @ strip . and all out strip . for what you have i woud go with, Hd rv type so it is firm this take some slip out and work good

OK,
Thanks blue and pat,

Somebody correct me if I am wrong.

The factory manual (one the GM dealership technitions use) shows purely stock components. Now, in their picture they are showing a valve body to spacer plate gasket, the spacer plate, and a spacer plate to housing face gasket. My set up has only a one piece plate with gasket type material on both sides that I previously tried to remove and made a comment on earlier. Is this what is supplied in shift kits?? I looked on Summits page at shift kits and it shows these same type separation gaskets (plates) with 3 options.

I have never seen a kit before so I dont know. If this is correct, then I suppose the overhaul kit I ordered is going to come with the gaskets only and not the actual plate so I will have to either reuse this one (if I didnt damage it trying to remove the seal material) or order another shift kit???

the plate comes in the kit and the gastkets

Originally posted by pat mccarthy
the plate comes in the kit and the gastkets

you are referring to shift kit or overhaul kit?

Originally posted by s10streeter
you are referring to shift kit or overhaul kit?

the shift kit comes with the plate and gaskets. the kit will tell you what you need to know when you buy it .do not get the shift kit gaskets mix up with the one in your overhaul kit

After disassembly and inspection it seems that I am going to need a direct clutch pressure plate, overrun clutch support, and possibly a new forward drum. The steels in the direct clutch assembly were scored up pretty bad. Guess I found out where the metal in the pan came from.

Could anyone recommend a quality supplier?? Are these parts still available new since this is a trans from the 70's???

I would rather not go to the boneyard.

THM 350. Non lock up.

Got the parts I needed from local trans shop. Had to have a pump as well. Got all internals in, ready to install valve body and pan.

Not sure I will stay with this trans though. It seems this is a six cylinder set up. Only 4 first and reverse frictions and the manual shows all v-8 set ups to have 5??

Anyways, I hope the performance frictions and steels that I used will help extend the life span until I can buy a name brand performance TH350.

Waiting on TCI to recommend a convertor so I can get it ordered.

A heads up to anyone that is up to attempting this like I did for the first time without proper knowlege for specific tools that are needed: Be very careful with the retaining rings, always wear eye protection, had one come flying out of the case popped the lens on the saftey glasses I was wearing, good thing I had them on, that could have been nasty. And if you can, get a manual, there are a few critical clearances that need to be measured. You may get a working unit without checking, but the risk for premature wear is great. It is also difficult to install bushings without the proper tools, once again it can be done but chances are you are going to need a file to get rid of the "flat spots" caused by hammering. Out of luck a mechanic I know had a tool that was made for compressing the springs and retainers for the piston in the bottom of trans, without it I dont know if I could have gotten it out. C clamps work pretty good on the pistons in the drums but you have to be very careful on setup not to have uneven pressure on the retainers or they will bend and keep an eye on the lip of the retainer during reassembly that it doesnt hang up on ridge of drum. This backyard to storage shed "mock" trans shop is no fun indeed. Praying for success.

After struggling with a kickdown to case leak issue, finally on the road again and not having any trouble.

Thanks for everyones suggestions.