rayfrausto

I need a little help, from what I'm reading a th400 slip yoke will work in place of the bolt on 4l80e yoke. The driveline shop building my driveshaft has a th400 32 spline yoke that is counterbored with no splines in the beginning of yoke. I'm reading this is what I need. Just wanted to make sure and give them the go ahead to put that yoke on

truckdoug

iTrader: (25)

yeah that oughta work. post up some pics of the output shaft and I can tell you for sure.

rayfrausto

Oh okay so I still have to remove tail housing? I was thinking the counterbored one will work on either shaft. I was just hoping I could get an answer without doing that cause tranny is already installed in car and I won't be able to get to the car till Sunday to finish some work on it, but driveshaft would be ready tomorrow for me. Maybe I could tell him to just hold off on putting on the yoke till I verify it.

twinturbo496

iTrader: (2)

You need to be careful if you have a fixed yoke type shaft in the transmission.

rayfrausto

I'm sorry but could you elaborate more on this please and thank you?

DW SD

I would install a proper 4L80 yoke. I have a 6L80. the TH400 yoke was installed on my driveshaft initially, but was much shorter than the 6L80. It didn't engage deep enough to be fully supported by the bearing in the tailshaft housing and vibrated badly. I picked this up running on a lift.

You can find the right part # through rock auto or parts.com or one of the GM ecommerce sites.
I sourced mine by looking up yoke application for 3/4 ton gas Silverado pickup truck, 2WD of the right year.

Doug

truckdoug

iTrader: (25)

there are several different types of output shafts. this link shows just a few...i think there are 8 or 9 total.


http://www.pirate4x4.com/forum/attac...-dsc00132.jpeg


you can use the counter bored yoke on a couple of them. i had to remove an o ring from mine to make a slip yoke work.

rayfrausto

Thank you guys for your help. So I didn't have work today and drove to go remove tail shaft housing and look at output shaft. I took a picture to make it easier.




Sorry for picture quality my camera on phone is garbage. But here is my output shaft so witch yoke do I get to make it a slip yoke?

rayfrausto

The right yoke is a bolt on yoke? I thought these were used in trucks for how much suspension travel they have. I thought I would want a slip yoke for my cutlass

DW SD

Yes. It is a slip yoke.

rayfrausto

So comparing my picture to a couple of serches, has me to believe I can use a normal slip yoke on my style output shaft. So I want one fully splined not counterbored?

DW SD

Sorry. Don't know what my output shaft looks like behind the tail shaft housing. Do you know the OEM application? If so why not just buy the stock slip yoke?

Doug

truckdoug

iTrader: (25)

that is a fully splined shaft. you can use a fully splined yoke or the counter bored one your driveline guy has.

DW SD

I commented on a previous thread with a photo of the 6L80 yoke vs. TH400 originally installed.
A quick read here might help explain (the photo tells ): https://ls1tech.com/forums/conversio...-question.html

Here is the picture (6L80 is the long one). I would suspect the 4L80 is similar.

rayfrausto

Well thank you guys for the info. I went and paid the driveline shop a visit. Showed him the picture and discussed basically what we were talking about here, he pulled out a yoke same size as the TH400 one pictured above with no splines in the beginning of it, he told me this is the one I want to use, so I went with his suggestion