TH400 going out in my 89 C2500

[Sean Buick 76]

I get the TV cables from the GM dealer

 

[Erik the Awful]

My '88 C3500 originally came with the TH400 as well, but the drivetrain is missing. I managed to find a 4L80 cheap on Market Place, but if I couldn't, it would be TH400 or nothing. The 700R4 is barely enough for a C1500.

If you go with a 700R4, take the time to set the TV cable up properly, with the pan off, and then use a pressure gauge to verify before driving it.

Here's Performabuilt's excellent video on setting up the TV cable with the pan off.

xc_hide_links_from_guests_guests_error_hide_media

Here's my video, which comes across like "this is what it looks like when an idiot tries to follow Performabuilt's instructions".

xc_hide_links_from_guests_guests_error_hide_media

 

[BigBen]

Replace the TV cable with a new one - do not pit that old-ass decrepet cable on to your vehicle/trans. Also you'll need the bracket.

Take that pan off and inspect the underside and what's at the bottom of the pan. If nothing alarming or damge is observed put it back on with a few bolts and yank it. Put a diff pan on it later.

Lastly, make sure you do a pressure test before trying to drive it so you can confirm/deny TV cable set up and adjustment are good.

Got to the pick n pull a bit late in the day, but here’s under the pan doesn’t look too bad.
Also didn’t realize you can’t bring a jack to a pick n pull so I might have to get creative

 

[NickTransmissions]

Got to the pick n pull a bit late in the day, but here’s under the pan doesn’t look too bad.
Also didn’t realize you can’t bring a jack to a pick n pull so I might have to get creative

Did you attempt to attach a picture? If so, it didn't post.

Use an old tire...Place it under the trans then remove everything that you have to in order to drop the pan. Once you remove the bell housing-engine block bolts, the trans should just fall onto the tire.

 

[BigBen]

Did you attempt to attach a picture? If so, it didn't post.

Use an old tire...Place it under the trans then remove everything that you have to in order to drop the pan. Once you remove the bell housing-engine block bolts, the trans should just fall onto the tire.

Yeah just sent, my bad my connection out here isn’t the best. Got the drive shaft out, they have this big crane i think I’ll just pull the whole engine

 

[BigBen]

New transmission secured! probably won’t update for a while until I have more time+money for the other things. Will say taking out the transmission with the engine is a whole world easier than dropping the transmission.

 

[NickTransmissions]

New transmission secured! probably won’t update for a while until I have more time+money for the other things. Will say taking out the transmission with the engine is a whole world easier than dropping the transmission.

Will you be overhauling the unit?

 

[BigBen]

Will you be overhauling the unit?

Been thinking about this and I wasn't going to at first because I don't have the money right now. The thing is I won't have time to swap in the new transmission for a while and I'm planning on having this truck as long as it will last so I think overhauling/rebuilding it would be a good idea, I have to wait anyway so I might as well save up some money to do it right.
Do you have any recommendations on what to do/where to learn how to do it? My dad is a mechanic so we have the tools but he wont be able to help for a while so I'd like to learn.

 

[NickTransmissions]

Been thinking about this and I wasn't going to at first because I don't have the money right now. The thing is I won't have time to swap in the new transmission for a while and I'm planning on having this truck as long as it will last so I think overhauling/rebuilding it would be a good idea, I have to wait anyway so I might as well save up some money to do it right.
Do you have any recommendations on what to do/where to learn how to do it? My dad is a mechanic so we have the tools but he wont be able to help for a while so I'd like to learn.

Yep - you can check out my 700R4 Info thread which has all sorts of info, links to my rebuild series and tear down vids as well as other resources...check out the videos to get a sense for the nature and scope of the work as well as what special tools you may need to acquire.

Let me know if you have any questions once you've had a chance to view or when you begin...