so over the weekend, while merging into traffic, my built 4l60e went boom on the 1-2 shift.

i have reverse, but no forward gears. trans has always run between 160-172 degrees during city driving, and as low as 135 degrees on the highway. fluid was changed after break-in per the builders instructions. i was running standard dex6 fluid in the unit.

any ideas as to what broke? trans only has 5600 miles on it.

i have been in contact with the builder, and am getting ready to remove and ship the trans back to them. i would rather not say who the builder is, as not to cause them any issues.

 

That sucks. good luck getting it worked out.

 

Broke input or output shaft maybe..

 

Cracked piston maybe, or sprag or bad pump. Sorry to hear that

 

these built units are going down fast these days.

 

especially considering that my truck is far from the heaviest vehicle that a 60e has been put in. landfill scale says 5020lbs with a nearly empty fuel tank.

i know there are guys here with lifted, eclb trucks with oversized tires and far more power than me that don't break built 60e's, so i'm not sure why it broke.

i don't think my 4.8 w/ exhaust is too much for it...

 

Mine broke from 1-2 shift,and it was the sprag. I still had gears 1,2,3 though along with reverse...Atleast thats what the trans's shop told me is what broke.

 

yea, its been like that forever, you notice it more and more now that's all. Ive been a advocate for the 80e swap. My theory with the 60e is it will not hold long at all with numerically lower gears than 4.10s. Alot of guys run 3.42s, 3.73s with the 60e and it bites the dust even quicker combined with our weight and big wheels.

A 60e with 4.10s, 4.56s etc will last alot longer in my opinion. Just something I noticed.

 

Sounds like you broke the output shaft... Mine did the same thing about 3 weeks ago...

 

wouldn't that prevent the truck from having reverse and park? because then the shaft would just spin...

i don't claim to know how the internals of an auto trans work, but from all the threads i've read about the 4l60e it seems that the sprag or the input drum are the likely culprits here.

sleeper mentioned gear ratio playing into it, i have 3.42's out back, and since its 4wd i don't wanna spend $1k or more on a gear swap.