Dana 70 question

[rdodd]

My 92 ctd with 3:55 LS rear end has always made some noise when making turns but lately it even kind of shakes the whole truck when idlying around a corner. Is this condition normal with LS rearend? I have always changed the fluid with 80-90 gear oil and have added as much as 8 oz. friction modifier and do this every 30-40 thousand miles. Can more than 8 oz of the snake oil be added to prevent this vibration and noise or is there a limit on how much is added?

 

[dpuckett]

Having been down this road twice in Mom's truck (thanks to Hart TIre of Poplar Bluff for the second time), I'd say if it is shaking the wole truck around corners, it's too late for any additional friction modifier to help it. You need to put in a new set of clutches. They arent that much for the set if you look around at some medium duty truck shops. Personally, I change all the fluids at least once a year. I think I do the rear diff about every 25-30K. I'll have to let you know in 6mo; never had a single vehicle that long.

 

[rdodd]

If the clutches were bad wouldnt they be making this shaking all the time. Some times i drive all day without this noise or shaking. What is the recommended amount of friction modifier that should be added. Can too much be installed?

 

[jbolt]

Rodd-



Over use of the friction modifier will only reduce the effectiveness of the limited slip. Last time I did mine I had to put in about 12oz before it felt okay. It is still a little tight sometimes but not enough to worry about. I've talked to a few folks who have put in as much as 16oz.



Jay