4l60E Mods
Thread Starter
Teching In
Joined: May 2017
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4l60E Mods I am getting ready to rebuild my 4l60E what are some mods I can do while I'm in there this will be for my towing vehicle. I remember seeing something about drilling the valve body plate but can't find it anywhere.....
Thanks Mark
Thanks Mark
Last edited by markhodges78; May 14, 2017 at 08:43 PM.
What are you driving (vehicle, horsepower, etc)?
Is this strictly daily driver with some towing or will it also see a track?
What's your budget, and does that include getting a new torque converter?
Have you rebuilt a transmission before?
Is this strictly daily driver with some towing or will it also see a track?
What's your budget, and does that include getting a new torque converter?
Have you rebuilt a transmission before?
Thread Starter
Teching In
Joined: May 2017
Posts: 42
Likes: 2
This is a stock 2003 Yukon XL I have rebuilt several 4l60 and 4l60e but I have never done any mods other then drilling the drain hole behind the pump seal .... I just got this vehicle and I was originally led to believe that this was a 4l80e then once I picked it up I found it was a 4l60e ... This will be used to tow a camper and boat....
I'm sure others will chime in, but beyond the usual things to do during a rebuild of a stock unit (like a shift kit and new clutch packs) I'd say both the Sonnax 2nd and 4th servos, heavy duty 2-3 shift valve, transmission cooler, and a wide band.
Teching In
Joined: Apr 2017
Posts: 47
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From: Oregon
I saved a few quotes from different forums that talked about the holes for truck / towing applications. I didnt save the complete post so I cant tell you who's the author, sorry.
With the stock diameter torque converter, the 2nd gear feed hole in the separator plate (this is with the Corvette servo) should be .076" with .086" maximum. The part throttle shift will get too firm with anything larger than this, and will be very hard on the splines on everything in the gear train.
A .093" orifice will give you a nice, firm 2-3 shift with the 3-4 clutch setup listed above and a Corvette (or better) 2nd servo set up at about .070-.080" servo travel. I use a .110" in many street rod setups. A .125" orifice will work well with a very loose converter, but would be pretty abusive in a truck application.
For other parts just for a quick list Sonnax's HD build list is an easy link.
http://www.sonnax.com/tech_resources...charts#pickups
They just released the #74140-01K last week.
