I am in the middle of my 60-80 swap and took my stock driveshaft to get 2 inches removed. I read everywhere that you need to move your crossmember back 2 inches, so I was guessing that the 80 was 2 inches longer over all and needed a shorter driveshaft.

Is this the case?... if not I need to know before he cuts the driveshaft in the morning!

What got me worried was this image...



Anyone that has done this swap or knows the answer please let me know!

 

This is whats needed for the 4l60e to 4l80e swap! - LS1TECH

This thread also states that the driveshaft length doesn't need to be changed. Still waiting for some input from someone with hands on experience.

Thanks

 

I would just wait until the 80E is in and the truck is at ride height...

 

FWIW, I was able to reuse the stock driveshaft when I put an 80E in my RCSB.

 

Looks like I need to call him in the morning and just get him to install the conversion joint / yoke and leave the length alone!

He is going on vacation all next week and I was hoping to be driving by monday, that's the only reason I was trying to go ahead and get this shaft done.


Thanks

Anyone else can pitch in too to confirm this or say otherwise.

 

So after reading a lot more threads about the stock shaft working fine I decided to take some measurements. And this is what I found
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I measured from where the 80 mounts to crossmember to the end of shaft is about 2"

I measured the same on the 60 from crossmember to end of shaft is 7.5"

The 80 crossmember is 2" further back than the current crossmember so the difference would be like 3.5"

Am I looking at this wrong or something?

So now I'm more confused than I was to begin with.....

Plus I messaged a member on the forum and he says that the shaft needs to be 1.5" shorter..... but none of this is making sense.
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I think I read athread the other day about that swap and you needed to add 4-more inchs to the crossmember...? Maybe I should go back and read again though,But that is what some said..They were able to use there same driveshaft,and others went out and got another one.

 

On a 2wd my understanding is that you have to move the crossmember back 2". I think a 4wd is more along the lines of 4". I do know that you have to get new driveshafts on 4wd, but 2wd is still mixed stories.


I've also seen a lot of people buying aftermarket shafts.... but I don't know if they did this because they wanted a "better, stronger" shaft or if the stock shaft was not the proper size in stock form.

Also note that my measurements make it appear that I'd need a LONGER shaft.

 

The crossmember goes back way farther than 2". It's more like 6 or 7 inches.

 

Makes a lot more sense now... I'm not sure why I was thinking 2" I've read over every 80 swap thread for like a year now.

So the math basically says that if the trans moves back 5.5" the stock shaft will work... this isn't taking into account that the yoke of the 60 sticks out a little further than the yoke on the 80 so that may give some extra room.

So I guess I should just go get the shaft tomorrow in stock uncut form and try it out...

Thoughts?