Buying a rebuilt transmission th350

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Zelph

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All turbo 350 are 27 spline output.
Check how far the output shaft sticks out. 2.5 inches is correct for the 208.
The 203 and 205 are 7/8” from the back of the case.
Do you know how to tell the difference between a 2wd case vs a 4wd case?
If this rebuilt trans is from the vehicle as described it would be a direct replacement.
 

HotRodPC

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I'd definitely rebuild your existing unit if the guy wants $750, unless he has paperwork showing exactly what was installed, all the parts that should have been installed were installed, when the work was performed and how many miles at the time of the rebuild as well as a means for you to compare that mileage figure to the vehicle it came out of to see how many miles are on it...This assumes it's not a fresh rebuild that has never been installed into a vehicle since it was overhauled. If that's the case, you just need a build sheet showing exactly what was installed.

You can check out my TH350 Playlist on Youtube for rebuild instructions, topical videos and other tech information on those units.
Agreed. That seems pretty steep for a Th350. Especially to know it might not fit becuase Th350's came in front NP203, NP205 and NP208 was rare. So without mathing up the output shafts, how certain is it that it's going to work.
 

HotRodPC

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Thank you and if I may ask just one more question. My transfer case is a 208 I'm assuming that my transmission must already have an adapter for the 208? I have been reading that the out put shafts are different for the 208 as opposed to the 203 and 205? Is that correct?
Yes, the output shafts are different.
 

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Yeah the fluid was burnt there was a lot of sludge and burnt clutch at the bottom of the pan metal shavings. Just thought it would be handy to have one around if mine started to act up
So yours is acting fine at this time? What do you mean by alot of sludge. It is totally normal to have some sludge in the pan and some glitter from worn metal parts. You just have to know how much is about normal, but I've seen a small pile of sludge and plenty of glitter in Th350's with brown fluid and the person didn't have money for a rebuild so it was put back together and they continued to drive it for many more months that I know of for sure. Not sure what point it gave up. Th350 and Th400 are quite tolerable even when well worn.
 

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Basic handtools, a workbench, good lighting and an ipad or laptop nearby, most anyone can rebuild a turbo 350. In my younger days, a transmission was some voodoo science I thought I'd never understand. Today, you can literally wrench, pause and play your way thru hundreds of youtube videos from pros like Nick as they walk you step by step thru a tranny rebuild, and you won't have to worry about interchangeability.
 

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Basic handtools, a workbench, good lighting and an ipad or laptop nearby, most anyone can rebuild a turbo 350. In my younger days, a transmission was some voodoo science I thought I'd never understand. Today, you can literally wrench, pause and play your way thru hundreds of youtube videos from pros like Nick as they walk you step by step thru a tranny rebuild, and you won't have to worry about interchangeability.
Thanks for the info I might have to try it
 

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So yours is acting fine at this time? What do you mean by alot of sludge. It is totally normal to have some sludge in the pan and some glitter from worn metal parts. You just have to know how much is about normal, but I've seen a small pile of sludge and plenty of glitter in Th350's with brown fluid and the person didn't have money for a rebuild so it was put back together and they continued to drive it for many more months that I know of for sure. Not sure what point it gave up. Th350 and Th400 are quite tolerable even when well worn.
Yes seems to be acting fine, I put a new filter and fluid the pan gasket was leaking that's why I changed it. First time changing my own transmission fluid and was very surprised by what I saw might have freaked out a little. The reason I thought about buying this transmission was because it came with a transfer case and fluid a drive shaft and transmission cross member. Seemed like a good deal for 750 but none of it would work with what I have. It was a 203 transfer case I have a 208 and so the transmission would not work as well. Just did not want to be kicking my self if my transmission started acting up and I could have got a rebuilt one with 0 miles for a decent price.
 

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Thanks for the info I might have to try

I can't answer your question about the spline for transfer cases but there are differences in tailshafts and it is important to get the right transmission to fit your truck. TH350 internals are the same there are case and other variations.

If you are handy and can follow instructions there is no reason you can't rebuild your current transmission. The TH350 is a very simple unit and easy to rebuild for beginners. You can buy upgraded parts and build yourself a pretty bullet proof unit for $750. If you are comparing $750 to a store bought rebuild then it is a good price.

My original transmission cracked last year. The truck has rolled over a few times. Not sure how many. The transmission still worked but was leaking fluid like a sieve. I could not find a used case or unit for a reasonable price, so I ended up buying an Auto Zone rebuild. If it dies at some point I will just rebuild it myself.
Thank you I did not realize that rebuilding my transmission might be something I could do myself. This a great forum, I might have to check out Nick's youtube and give it a try. Would be really cool to rebuild my own transmission for a good price. Thanks
 

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Yes seems to be acting fine, I put a new filter and fluid the pan gasket was leaking that's why I changed it. First time changing my own transmission fluid and was very surprised by what I saw might have freaked out a little. The reason I thought about buying this transmission was because it came with a transfer case and fluid a drive shaft and transmission cross member. Seemed like a good deal for 750 but none of it would work with what I have. It was a 203 transfer case I have a 208 and so the transmission would not work as well. Just did not want to be kicking my self if my transmission started acting up and I could have got a rebuilt one with 0 miles for a decent price.
Yes seems to be acting fine, I put a new filter and fluid the pan gasket was leaking that's why I changed it. First time changing my own transmission fluid and was very surprised by what I saw might have freaked out a little. The reason I thought about buying this transmission was because it came with a transfer case and fluid a drive shaft and transmission cross member. Seemed like a good deal for 750 but none of it would work with what I have. It was a 203 transfer case I have a 208 and so the transmission would not work as well. Just did not want to be kicking my self if my transmission started acting up and I could have got a rebuilt one with 0 miles for a decent price.
There was a lot of clutch material and glitter enought to scrape out with a putty knife
 

Edelbrock

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Yeah the fluid was burnt there was a lot of sludge and burnt clutch at the bottom of the pan metal shavings. Just thought it would be handy to have one around if mine started to act up

Your current trans is still working properly? My advise would be to stop right there. Crud in the trans pan is normal, and does not mean that there is a problem. Now if your transmission starts acting up, then you would want to start looking for a replacement. What if you buy that spare transmission and your current one lasts forever? Or if you crash the truck next week totaling it. As for rebuilding yours, don't fix it if it's not broken.

Another note on crud in the pan:

Ever cut open a used oil filter before? You would be amazed on what is in there, and your first thought would be that the engine is shot. Nope, the filter is there for a reason and there is a reason that they need to be replaced regularly.
 

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Your current trans is still working properly? My advise would be to stop right there. Crud in the trans pan is normal, and does not mean that there is a problem. Now if your transmission starts acting up, then you would want to start looking for a replacement. What if you buy that spare transmission and your current one lasts forever? Or if you crash the truck next week totaling it. As for rebuilding yours, don't fix it if it's not broken.

Another note on crud in the pan:

Ever cut open a used oil filter before? You would be amazed on what is in there, and your first thought would be that the engine is shot. Nope, the filter is there for a reason and there is a reason that they need to be replaced regularly.
Great advice, thanks. I just never realize how ugly it could look in a transmission pan. As far a fixing thing that are not broke I do have a tendency to try to get a head of things that may never happen lol. Thanks for the help.
 

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