1998 4L60E & 2005 4.8 LS

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Donnan

Newbie
Joined
Sep 9, 2021
Messages
10
Reaction score
4
Location
Stirling Ontario Canada
Hey everyone looking for info if I can use my low mile 137,000km 4L60E original transmission with a 2005 4.8 LS SWAP hopefully someone with more engine transmission knowledge then myself will chime in on the discussion
You must be registered for see images attach
 

stutaeng

I'm Awesome
Joined
Aug 7, 2019
Messages
3,410
Reaction score
4,348
Location
Dallas, TX
Yes, I believe it can be done, but it's around $300 in parts IIRC.

I "think" you can do some spacers between the TC/flywheel bolts and elong the TC holes on your flywheel...kinda the redneck way of doing it.

I would use that money and just get an LS-style 4L60e. They have stronger input shaft, a larger 300 mm torque converter (reason why you need the spacers on your tranny) and some better friction plates.

xc_hide_links_from_guests_guests_error_hide_media
 

Donnan

Newbie
Joined
Sep 9, 2021
Messages
10
Reaction score
4
Location
Stirling Ontario Canada
Thanks, I guess the biggest hang up I was wondering about was the pcm talking to the 98 transmission.. that was my main concern. I was thinking about putting in a 4L80E, I want to really keep the interior stick with the electronic push button 4wd any advice??
 

stutaeng

I'm Awesome
Joined
Aug 7, 2019
Messages
3,410
Reaction score
4,348
Location
Dallas, TX
PCM should not a be a problem. I'm pretty sure they are the same electronically. At some point late on the production run they added an input speed sensor (this may be on the 4L65e though?)

I personally did a 4L80e swap on my 1500 2wd NBS and don't regret it. It's a great transmission.

What transfer case do you have? I'm sure there's an adapter that will bolt to your TCase. I also don't know if driveshafts need to be adjusted on the swap (80e is longer.) Just get a 80e 4x4 model, not a 2wd.
 
Last edited:

Donnan

Newbie
Joined
Sep 9, 2021
Messages
10
Reaction score
4
Location
Stirling Ontario Canada
Not sure on trans case at the moment it’s an SLE Sierra 4L60E with push button electric trans case control all factory oem equipment with a 5.7 vortec in front of it
 

stutaeng

I'm Awesome
Joined
Aug 7, 2019
Messages
3,410
Reaction score
4,348
Location
Dallas, TX
That's a nice truck BTW! And welcome!

Why are swapping the engine anyways? Is yours worn out?
 

Donnan

Newbie
Joined
Sep 9, 2021
Messages
10
Reaction score
4
Location
Stirling Ontario Canada
It’s low kms 137,000 looking at the long run get way better fuel mileage with a tuned 4.8 LS Plus make some huge horsepower on 87 fuel Thanks for the compliment on the truck I think I found the unicorn still has the original window sticker from 98 lmao and all documentation.
 

stutaeng

I'm Awesome
Joined
Aug 7, 2019
Messages
3,410
Reaction score
4,348
Location
Dallas, TX
It’s low kms 137,000 looking at the long run get way better fuel mileage with a tuned 4.8 LS Plus make some huge horsepower on 87 fuel Thanks for the compliment on the truck I think I found the unicorn still has the original window sticker from 98 lmao and all documentation.
Oh, dang! I just realized the metric mileage, LOL. That's low!

In that case, I personally would just leave it alone. Nothing wrong with running the engine you have. I can understand a high mileage, worn out SBC getting swapped for an LS mostly just due to cost (junkyard LS is cheaper than machine shop-ed SBC,) and other reasons, but not a low-mileage runner. Go find yourself a beat up RCSB and drop your LS on that! Or better yet, just get a NBS with one already installed.

These trucks don't get spectacular gas mileage, LS or SBC. They are after all pretty darn heavy. Unless you go turbo over NA, I don't see a reason. I'm sure you have a plan, so don't let me steer you otherwise, LOL. Just my opinion.

I hope I helped answer your initial questions. And since you mentioned it, more reason to go with the 80e series if you go boost. ;)
 
Last edited:

Donnan

Newbie
Joined
Sep 9, 2021
Messages
10
Reaction score
4
Location
Stirling Ontario Canada
Yeah I feel you man, I bought it as cheap insurance $650 for a complete 4.8 wiring harness and all better then building a 350, I laid waste to three 350’s in my teen yrs and it didn’t take much lol haha that being said I don’t like them I’m a firm believer in the LS, unfortunately where I’m from gems like the truck I found don’t come along very often, especially 99-07 they rotted fast up here what I’ve got is a keeper I think she’s minty fresh diamond in the ruff thanks for the input I’ll stay in touch !!
 
Top