i have a 4l60e..can anyone explain to me why it doesnt go into 4th under WOT is the overdrive gear just not strong enough to take it? with my 4:10 gear and 275/45/20's i can only do 120 in 3rd and thats at damn near 6ooo rpms..i've seen alot of youtube vids of silverados hauling *** through all 4 gears and would like to know how its done..
thanks for reading

 

I wouldn't do it. It's hard on your tranny.

 

oh alright its not necessary in the 1/4 mile anyway lol thats what im really worried about but id be nice to know i can hit 120mph+ if needed

 

It's a tuning thing I believe. The 4th gear can't is a weaker gear due to the ratio's. Kinda risky doing it.

 

The 3-4 clutch pack is only about 4 inches in diameter with 5 or 6 plates IIRC. Mine let go just pushing resume after passing a truck. I was in third and holding fine, I hit resume and it went to 4th then to 5000 rpms. Now then with a 4L80E the clutches are huge and you can get away with it.

 

its in the tuning probably

 

if you run a triple disc converter you can shift into OD at WOT other wise you'll blow apart you stock converter,and yes it is set by the tune.
post links to said silvy's burnin through all 4 gears

 

Do you have tires and drive shaft for 120+ mph?

 

yeah in the stock tune the shift mph is set to 255mph for wot and 4th gear. and to like 8192rpm for 3-4 wot rpm shift

 

You def don't need a triple disk to do that..

I do believe it is in the stock tuning..