4l65 tranny
 

I'm doing an LS swap on my '70 Jimmy. I bought the setup from justchevytrucks. I got the 6.0 LQ4, 4l65 transmission, 208 xfer case, stand alone wiring harness and accelerator pedal. My question is what do you guys think of the 4l65 tranny? I had never heard of it before, all you ever hear about is the 4l60 and 4l80. I'm assuming the 65 is just and inbetween version but why does it seem to be a lot more rare? Does it hold up well? Is the physical size the same as the 60? It's already purchased so hopefully ya'll have good experiences with it. I guess it would have been smart on my part to ask these questions prior to ordering it but oh well.

Re: 4l65 tranny
 

Same case size as a 4L60E. Just upgraded to handle a bit more torque. I think 5 pinion planetary and better clutches?

Re: 4l65 tranny
 

Extra planetary gear is the big part, I think. But it's not just that, as I had my 4L60E upgraded to 4L65 spec at rebuild time, there are a lot of improved parts.

Re: 4l65 tranny
 

5 Pinion Input & Reaction Carriers, Hardened Stator Splines, Heat Treated Sun Shell & 7 .065" 3-4 Clutches vs 6 .080" 3-4 Clutches found on 4L60E's.

Truth be told.....They burn down at a greater frequency than standard 4L60E's because the thinner .065" 3-4 Frictions. 4L60E 6 .080" Friction stacks are proven to hold up better. To run a 7 Friction stack, It is better to thin the Steels from .095" to .077" & run .080" Frictions.....

The 5 Pinion Carriers are nice pieces, But 4 Pinion Carriers will handle 500 horsepower. Carriers fail from Torrington bearing failure that GM did NOTHING about with the 4L65E.

The Stator & Sunshell are good things, There are stronger Sun Shells out there though.