'97 C1500 4L60E to 4L80E Swap

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df2x4

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Just found out that Denny's Driveshaft offers free alterations to any of their custom driveshafts for life. That's starting to look like a great option.
 

shovelbill

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Just out of curiosity... I know a custom driveshaft would be expensive, but that would pretty much eliminate any further complications like conversion U-joints right? Would it be stupid to do something like that now if I'm planning on swapping a 14 bolt SF rear end in down the road? Just throwing some ideas around.


just from what i've "heard".....a conversion u-joint will work for a 14b swap......which as you know i plan on doing....

just for ***** sake........when i had the 4L70 swapped in we ended up needing to use a conversion kit for the torque converter that was built by Hughes for my truck.....was supposed to be a "conversion" converter to marry the Vortec motor to the LS trans........bullshit. had to buy the adapter kit........it set the trans/transfer case back 5/8th of an inch...my front shaft was fine....the rear APPEARED to be fine as well.......well, a few thousand miles later i noticed a few drops of trans fluid on the floor......

hmmmmm.....crawled under to check. the rear seal was leaking......hmmmm......turns out after hard driving in Zoo Yawk ****** the joint was hitting the tailshaft on the spline.......never woulda thunk that, but it did.........a seal is nothing at this point, but when i swap in the 14 bolt i'll be getting one built for MY application.....with a non-conversion u-joint too. my opinion is it's money well spent considering how much i spent already.

for now i deal with the tiny seal leak
 

df2x4

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just from what i've "heard".....a conversion u-joint will work for a 14b swap......which as you know i plan on doing....

just for ***** sake........when i had the 4L70 swapped in we ended up needing to use a conversion kit for the torque converter that was built by Hughes for my truck.....was supposed to be a "conversion" converter to marry the Vortec motor to the LS trans........bullshit. had to buy the adapter kit........it set the trans/transfer case back 5/8th of an inch...my front shaft was fine....the rear APPEARED to be fine as well.......well, a few thousand miles later i noticed a few drops of trans fluid on the floor......

hmmmmm.....crawled under to check. the rear seal was leaking......hmmmm......turns out after hard driving in Zoo Yawk ****** the joint was hitting the tailshaft on the spline.......never woulda thunk that, but it did.........a seal is nothing at this point, but when i swap in the 14 bolt i'll be getting one built for MY application.....with a non-conversion u-joint too. my opinion is it's money well spent considering how much i spent already.

for now i deal with the tiny seal leak

Thanks for the input! Much appreciated as always. Considering Denny's Driveshaft offers free modifications for life, I think I'm going to go that route. After mulling it over for a few hours it just seems like the smart thing to do. That way when I decide to do the 14 bolt swap I can send it back to them and have them weld a new joint on the back end. I'm going to call my mechanic first thing in the morning and steer him in that direction. The only downside I can see at this point is that their wait time is listed as around a month. Not a huge deal, I'm sure my mechanic can find someplace to store the truck for a while. Wish I would have made this decision before I brought everything to him, though.

I'll bring him a couple dozen donuts and some beer for the inconvenience. :lol:
 

shovelbill

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i know you can find a reputable driveline shop somewhere near.....i have one by me and that's the route i'll be using.......how much is shipping 2 ways? consider that.

there are FANTASTIC internet shops specializing in driveline components for off road vehicles.....but do you really need that ?

just my $.03 and useless opinion.
 

df2x4

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That is a good point. I'll ask my mechanic when I call him tomorrow if he knows of any local shops that he'd prefer. Denny's seems to have a spectacular reputation among their customers, though. At this point I don't mind paying a little extra for some quality and good customer service.
 

shovelbill

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when i was in the towing business for 13 years back in the '80's, in Brooklyn.....most companies used Universal Driveline for their needs....including my company.....fast forward 20 years........i was back the that ******* city after my great escape....but

when i needed the front shaft rebuilt for my old '90 K/5, i went there.....and they still did the proper job.
and we reflected on my old company and the good old days when i was there.....i'll take quality a "neighborhood" shop all the time ....every time.

the old man that ran it was dead, but his son took it over and had great intgrity
 

df2x4

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Looking back at the terrible pictures I have of the 80E yoke (mainly the first one I posted of it in this thread) I'm beginning to see what my mechanic was talking about. It looks like my 80E may have a bolt on yoke. I believe he said on the phone earlier that my 60E used a slip yoke setup. No idea what the deal is there.

Regardless, I was looking through the Denny's Driveshaft website and they have slip yokes that they claim will work with 80Es which were originally equipped with the bolt on yokes. Bumped them up another notch on the driveshaft list as far as I'm concerned. I've seen about a 50/50 split of people on various forums saying that the threaded 80E output shafts will or won't work with a regular slip yoke. Here's a link to the Denny's slip yokes for anyone interested, the 80E stuff is down at the bottom of the page.

http://www.dennysdriveshaft.com/c75...32_SPLINE_TRUCK_TRANSMISSION_T_400_4L80_4L85_

I need to go to sleep.
 

df2x4

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So far it looks like I'll be getting a quote for a custom driveshaft with a 1350 80E slip yoke, and a 1310 rear U-joint to work with my 10 bolt for now. Looking at the 1350 joint for the front for a couple reasons. Mainly because it's the only size of those fancy 80E yokes in stock right now, but also because at a quick glance it appears that the 14 bolt SF rear ends use a 1350 joint. Would be nice to have the same size front and rear whenever I get around to doing that swap.

Apologies for bumping the thread so many times in short order, mainly just trying to organize my thoughts so I remember all this crap in the morning. If anyone sees anything I'm missing here please feel free to chime in.
 
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RDF1

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Very nice.
Ive found 1350 pinion yokes for the 10 bolt rear. That way you can use same joints front and rear.
On some stuff ive ran ******* joints where it will be 3R to 1350, and 1330 to 1350 and such.
 

df2x4

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Well I may have spoken too soon on the Denny's stuff. I'm sure that's what it'll get eventually when I end up 14 bolt swapping, but my mechanic has found a shaft locally that should work for us. $300 vs $700, so I'm probably going to go that route if possible. He's going to do some checking and make sure they have the appropriate slip yoke for it and get back to me in the morning.

EDIT - Also apparently I'm getting a new radiator. There's a small crack in the top that's leaking. Guess that means a fresh factory in-rad transmission cooler on the bright side!
 
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