I need to replace the Pinion Oil Seal in the rearend, i been trying to find out what Size is the Pinion Flange Nut? and what type of torque wrench should I use? oh yea I have a 2001 Dodge Ram 1500 with the 5.2L with the 9-1/4 rear. Also I havent been getting all that great MPG i been getting around 11MPG anything I can do to better it?

 

changing the pinion seal involves several less than normal tools:

a tiny inch-lb torque wrench to set the running preload near the end of the install. this is a crucial step to get right

a counter brace to hold the pinion shaft while the nut is untorqued, this is a big wrench that can brace against ground or frame

my memory is fuzzy on the MM size of the big nut,
but 2.25 comes to mind as what english size is just a bit bigger

there have been many past posts that owners who originally tried to untorque the big nut with a three quarter inch drive air impact wrench were unsuccessful, and had to go get a one inch drive impact

do a search on this website for the computer file pdf version of the 2001 model year Ram 'Field Service Manual' or FSM for short. It is well worth reading before tackling the pinion seal.

good luck

 

I just changed mine and it was 1and 1/4 IN. I carefully drove a screw driver thew the old one and poped it out and used a seal driver to put the new one in.

 

by the way 1997 2500 4.10 gears

 

What do you mean by set the running preload near the end of the install. My truck is a 1997 2500. Thanks

 

Do the typical stuff, like a tune-up. New plug wires, distributor cap, rotor, and plugs. Run some injector cleaner through; on your next fill-up, pour in some injector cleaner (one bottle or two, follow the directions) before you fill the tank.

Some minor things that sometimes help but not always: synthetic oil rather than regular, air filter/cleaner upgrade, better flowing exhaust, and so on.

Other than that, more expensive options: SCT tuner with economy tune, new "harder" tires (less rolling resistance), etc. etc.

I get 11 mpg in town right now with my 5.9L V8. Your 5.2L, depending on tires and driving habits, should be getting a couple more MPGs than that I would think.

 

ok thank you everyone that posted i will be changing it out this weekend when I have time.. I was a mother changing the water pump I found out on here how to I was having probs getting the fan off. then come to find out that wasnt even the prob the hose that went into the intake manifold had a cut lol oh well but again thanks.

 

I just have one more question what about the torque? thats the only thing im still kinda wondering about it says to check the torque before do i leave it on the ground or jacks? i def wanna make sure it gets the right torque..

 

when doing the step with the little inch-lb torque wrench to check the pre-load
the tires need to be off the ground

while it is true the differential will run for awhile by skipping this step
you are depending on luck to get by

preload on the pinion bearing has an effect
on how long both the oil seal and pinion bearing last
and also on MPG due to gear friction
and also how hot the oil in the diff gets

there are so many words and pictures in the FSM about the job
that is best to actually read and study it
yourself
or pay a professional $20 to $40 to go over it with you one on one
even if you want to do it yourself

good luck