Can anyone tell me if the rear end in an 01 1 ton requires friction modifier? Thanks

Yes. Look at the glove box tag,it should say. you can also call any dealer with your vin number and they will tell you how your truck was built.

Cool. Thanks man

if it has the limited slip yes, mine doesnt but that is fine, im dropping a detroit locker in it!

yes it will. all the 1 ton.s come with limited slip so anytime the diff oil is changed it will need some

Or get a gear lube with friction modifer already blended in.