zstewa12

Hi all. I am new to the whole online forum thing so i hope i am posting this in the right spot. I am a long time f150 forum stalker.

To make a long story short, I know there are a lot of post on the torque requirements for the rear pinion nut on the 2004-2008 f150s. None quite answer what i need. My vehicle is a 2006 f150 4wd xlt super cab 5.4l with heavy duty payload package. Today i had a leak coming from rear pinion seal. I didnt want to drive it as i knew it had been leaking for a few days but was significantly worse when i got to work this morning. I had a coworker take me to get the seal, and the 75-140 weight gear oil and i replaced the seal before i left work. In doing so i did a quick read on a post here and torqued the pinion nut to 160ft-lbs. and put it all back together.

Going back now i am seeing posts and info i had not seen before on finding the rotational torque to turn the wheels (in in/lbs) and torquing the nut in 5 lb increments to get that set back to what it was pre-seal repair to have the bearing preload set correctly.

So now i am having second guesses on this repair and i am wondering Is what i did completely wrong and can i expect my rear end to grenade now?

Phyer Phyter

The easy way to check is get an inch pound dial torque wrench and check your rotating torque. Make sure your wheels and brake drums are off so you are not experiencing any drag from them. I suspect you may not have tightened your pinion nut tight enough. While you have the drive shaft off try pushing up and down on the pinion yoke and see if you have any free play. You should not have any. You also don't want to over tighten the pinion nut either. If your rotating torque reading is higher than spec --- then you are probly in over your head to fix from this point and should take it to a shop that specializes in differentials and explain your problem.

zstewa12

Thanks for the reply. I had zero play after torquing to the 160 ft/lbs with the driveshaft off.

zstewa12

As far as internals, what could go wrong if it is too tight or too loose? Just trying to further understand.

greasyknuckles

if you tightened it too much you may have crushed the crush sleeve further which
puts too much preload in the bearings which means they may overheat and fail. if you
grab the pinion and turn it back and forth a little it should not feel tight with used
bearings. this "little" bit is not far just from the pinion hitting the ring gear on one side then the other. the measuring torque is done before removing the pinion nut and as you are reinstalling it until you get to the same number it was. the spec is 18-30in lbs
but that is with the carrier removed from the housing.