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4L60E transmission output shaft specifications


Full Member
Dec 16, 2003
Kingsport TN
By any chance does anyone know the dimensions or have access to a drawing of the output shaft for the transmission on the 1500 Avalanche?? I am working on a major modification and need the specifications on the spline shaft of the transmission.? I can not find those details in the shop manual nor have I had any luck in 3 days of searching on the web.? I need to buy a coupler and the manufactures want the exact dimensions on the splines, their angles and depth.?

I can reverse engineer but I would rather have the engineering dimension's rather than my micrometer measurements.? Thank you
Call Chuck at FLT Transmissions... he has a supplier making them outta 4340........ (y)
Where is FLT Transmissions?  I can not find them on the web and without a city or state I am drawing a blank.  Thank you.
dhrivnak said:
Where is FLT Transmissions?? I can not find them on the web and without a city or state I am drawing a blank.? Thank you.

Google is your friend..... :wave:


BTW, anytime you pick up a performance magazine and look at a Project car or truck, you can almost bet Chuck has built the tranny.....

dhrivnak said:
I thank you and found them but was not 100% sure they were the same.? I now know, thank you.

You are welcome my friend..... :wave:

Good Luck