4L60

[MtBraun]

Some background first. My son and I are looking at a 91 Chevy 1500, mainly for the snowplow that is currently attached to it. Owner will not separate the plow and truck. Owner says both engine and trans were "rebuilt", but you know how that goes without any paperwork. Anyway, he currently wants way too much for it considering the truck isn't drivable due to no brakes. We thought if it could be bought cheap enough we could potentially swap the trans/transfer case over to his 84 project, which is currently a roller.

Lots of Internet press about the 4L60E, but I can't seem to find much on the 4L60, other than it was made for 3 years and likely in the early TBI trucks.

What's the group's feelings on this transmission? I like the idea of a non-computer controlled OD transmission for this project. I know I can do the same with a 700R4, but seems a lot of guys here are not keen on it for a big tire, high torque truck application. Maybe the 4L60 is in the same class.

Thanks.

 

[74 Shortbed]

700R and 4L60 are the same, just renamed after all the factory upgrades.

 

[CSFJ]

Which style '91 chevy is this? V or K series? If it is the newer gmt400 platform, the t-case will have the drivers side drop instead of the passenger side that the squares use.

 

[twinturbo427]

4L60 and 700R4 for all real world purposes are the same thing with different names. The 4L60E is a different animal based on the 700R4/4L60 but electronically controlled, as you know.

I have rebuilt them in the past for 2wd applications and cars. I felt confident in replacing parts and adding shift kits. For my current truck I paid a lot of money to have a reputable shop build the 700r4 to better than stock, streetrod standards.

The weaknesses were worked out over the generations with updates, but it is still an econo tranny that must be built to be hot rodded or abused.

 

[MtBraun]

Which style '91 chevy is this? V or K series? If it is the newer gmt400 platform, the t-case will have the drivers side drop instead of the passenger side that the squares use.

Dumb question here, but how do I know? Of course I can crawl underneath and look, I'm more curious on knowing from the outside by looking at it. I don't have a grasp on the V's, K's, R's and all the other crap nomenclature used on these generations. Certainly willing to learn.

 

[MtBraun]

4L60 and 700R4 for all real world purposes are the same thing with different names. The 4L60E is a different animal based on the 700R4/4L60 but electronically controlled, as you know.

I have rebuilt them in the past for 2wd applications and cars. I felt confident in replacing parts and adding shift kits. For my current truck I paid a lot of money to have a reputable shop build the 700r4 to better than stock, streetrod standards.

The weaknesses were worked out over the generations with updates, but it is still an econo tranny that must be built to be hot rodded or abused.

So for this project I shouldn't view the transmission as anything other than a core for a future rebuild. We like stock transmission destroying torque.

 

[CSFJ]

Does this truck have independent front suspension?

 

[MtBraun]

Does this truck have independent front suspension?

Yes

 

[yevgenievich]

It has the wrong transfer case for your purposes. But motor/trans would be fine.

 

[twinturbo427]

So for this project I shouldn't view the transmission as anything other than a core for a future rebuild. We like stock transmission destroying torque.

It will make a great core, especially if it is a "K" case. Make sure to keep the cast aluminum flywheel cover and the support rods , if they are still with the truck.

If the tranny is in working order, use it! Get that truck on the road and drive it!

Like what was said in another post yesterday, we worry about getting things perfect and miss out on the fun to be had using the parts at hand.

 

[Crispy]

@Matt Braun

Quick cheat sheet:

K10 K20 K30 = 1973-1987 4wd trucks (C for 2wd)
V10 V20 V30 = 1988 4wd trucks (R for 2wd)
V1500 V2500 V3500 = 1989 Suburban for 1500 and 2500 and 1 ton truck which is 3500 only (R for 2wd)
K1500 K2500 K3500 = 1988-1998 trucks aka GMT400 (C for 2wd)

 

[MtBraun]

@Matt Braun

Quick cheat sheet:

K10 K20 K30 = 1973-1987 4wd trucks (C for 2wd)
V10 V20 V30 = 1988 4wd trucks (R for 2wd)
V1500 V2500 V3500 = 1989 Suburban for 1500 and 2500 and 1 ton truck which is 3500 only (R for 2wd)
K1500 K2500 K3500 = 1988-1998 trucks aka GMT400 (C for 2wd)

Thank you!