Rear Pinion Seal...how much?

[steved]

Well, how much does a rear pinion seal typically cost to have fixed at the dealer? Mine starting to leak...



I got to look at the manual, see if this is something I can do myself...

 

[Gus's 03]

it requires some specalty tools, inch/lb torque wrench, pinion nut socket ( 36mm 12pt if i recall) you'll also need a new crush sleve, a realy strong impact wrench.



if you dont allready have the tools, it'd prob cost less to have some one do it that allredy is eqiped for it.

 

[MountainMan1]

Sorry that I can't remember the cost but I recall being surprised at how quick and low priced it was.



What happened to me at a dealer was I went in for a new set of U-joints... I was later told the rear pinion was leaking. I knew it was sweating and had been that way for 10,000's of miles so I told them to not install it. There must have been a communication break down and the technician installed it anyway. The service writer came back to me and explained that I wound up with a freebee pinion seal install and how much I saved. My point is that it couldn't have cost them much in parts nor labor... I wasn't in there long for both jobs!

 

[steved]

Well, I couldn't find the pinion nut anywhere... so I got it ordered, and already got the seal.



I'm going to have a local shop (drivetrain-only shop) install it... quoted me between $100 and $150. Not worth my time sweating the details.

 

[WCounts]

Well, I couldn't find the pinion nut anywhere... so I got it ordered, and already got the seal.



I'm going to have a local shop (drivetrain-only shop) install it... quoted me between $100 and $150. Not worth my time sweating the details.

That's too much. The seal is expensive at arround $25-30 but is only a 30 min. job with the right tools. The yoke is quite tight with some sealant on the splines. Takes a puller. It's best to use the special seating tool that fits the seal. There's no crush collar . Just torque to specs.

Dealer changed my front pinion seal for less than $75 parts and all the last time I had to fluid changed.

 

[rbattelle]

Here's the procedure. Makes extensive use of the pinion wrench.

REMOVAL

(1) Remove axle shafts.

(2) Mark the propeller shaft and pinion flange for

installation reference.

(3) Remove propeller shaft.

(4) Rotate pinion gear three or four times.

(5) Measure and record the amount of torque necessary

to rotate the pinion gear with an inch pound

torque wrench (Fig. 20).

(6) Hold pinion flange with Flange Wrench 8979

(Fig. 21) and remove pinion flange nut.

(7) Remove pinion flange with Pinion Flange

Puller 8992 (Fig. 22).

(8) Remove pinion shaft seal with a pry tool or

slide hammer mounted screw.



INSTALLATION

(1) Install new pinion seal with Installer 8896

(Fig. 23).

(2) Apply a light coat of teflon sealant to the pinion

flange splines.

(3) Lightly tap the pinion flange onto the pinion

until a few threads are showing.

(4) Install flange washer and new pinion nut.

(5) Hold pinion flange with Flange Wrench 8979

(Fig. 24) and tighten pinion nut until pinion end play

is taken up.

(6) Rotate pinion several times to seat bearings.

(7) Measure pinion rotating torque with an inch

pound torque wrench and compare it to recorded

measurement. Tighten pinion nut in small incre-

ments, until pinion rotating torque is 0. 40-0. 57 N·m

(3-5 in. lbs. ) greater than recorded measurement.

(8) Rotate pinion several times then verify pinion

rotating torque again.

(9) Install axle shafts.

(10) Install propeller shaft with reference marks

aligned.

(11) Check differential fluid level.

Doesn't seem difficult at all, but there are quite a few steps. What's the chances of a shop doing it correctly? Depends on the shop, I suppose.



I assume an impact gun would be used to eliminate the need for the flange wrench?



On edit:

Looks like that flange wrench would be easy to make. Get a piece of 3/8" or 1/2" plate steel... piece of cake!



On edit 2:

The pinion puller is super-simple too! Use a bit of scrap from the flange wrench project and a big grade-8 bolt.



Ryan

 

[betterthanstock]

You can do it a lot more easily if you, after removing driveshaft, mark with paint the position of the nut, the flange , and axle. Then loosen nut and count exactly the turns. As it gets close to coming off the thread, pull on the nut so you know exactly where the thread ends, so you can count like 5 turns and 4 flats.



Then, when reinstalling, turn nut backwards while pushing on thread. As soon as it clicks, that's the start of your thread. Thread it back the exact number of turns and line it up with the paint, or go another flat past the mark.



And they don't tell you to sand smooth the flange surface where the seal sits, and to wash off the abrasive.

 

[rbattelle]

By BTS' method, you might not even have to measure the torque. Just count revolutions. Also means no need to remove the axle shafts.

Ryan

 

[sag2]

I always wanted to see a study of the number of ring and pinion failures on trucks that had the pinion seal changed vs. those that didn't. Most if not all technicians use an impact to reinstall the nut, and many do not use a new nut. My personal opinion is your just asking for trouble short cutting it. If it was as simple and easy as most technicians think, the procedure would read;

remove drive shaft

remove nut with large impact

remove flange with large swing press

change seal

install flange with big swing press

install nut with large impact, stopping after you think it's tight enough

reinstall drive shaft

Very few technicians have the 600 ft/lb torque wrench to properly tighten the pinion nut anyway, so thats why they use the impact. Luckily they get by most of the time, and the rest of the time it's in warranty so Chrysler can pay to replace the ring and pinion after it fails.

 

[WCounts]

That's the way the dealers do it.

 

[steved]

Cost doesn't matter... the local dealers suck around here... I'd rather go to a shop with a reputation than the dealers that have only ever taken me for a ride. And again, a lot of it has to do with timing... of which I have very little to spare.

Ryan: Thanks for posting that... I printed off the 04's FSM section too. The only thing I didn't have was the nut and inch-pound TQ wrench (I believe my grandfather has one, so I did actually have one to use).

 

[rbattelle]

Very few technicians have the 600 ft/lb torque wrench to properly tighten the pinion nut anyway, so thats why they use the impact.

I had no idea it takes that much torque!!



Guess I better start saving up for a BIG torque wrench! ... You know, just in case.



Ryan

 

[steved]

FYI, you only need 600+ TQ to initially crush the crush sleeve, it is significantly less to set the preload (after the sleeve is crushed). In my scenario, you probably need around 50#s to set the preload because you are only crushing the sleeve a tad more to get a couple inches of pre-load...



You don't actually need a TQ wrench to crush the sleeve, you simply crush it by "feel", and once it begins to crush you start judging pre-load. I think it is a holdover from early times to give an indication of the amount of force to actually crush the sleeve, so it gets crushed.



I have rebuilt several rears with crush sleeves, non ever needed a full 600 to crush. I have rebuilt a bunch of diffs, and to be truthful, I have only used a TQ wrench a couple times (all of those diffs are still running strong). Of any, I had access to a 600 TQ wrench when rebuilding my 9. 25 Corp, and never used it.

 

[DPKetchum]

I watched a tech in a busy G. M. store do diffs by feel. He had a ton of shims in his tool box,grey grease paint and brush. Could do a Z28 or Trans Am diff in 2 hours or less. Said he'd been doing a few a week for over a decade. MOST techs do the feel or mark the threads method in Dealers or independent shops. I use to explain the differance and price it both ways. Never had a customer pick the by the book way. Can remember TWO over 20 odd years that came back howling!!! They were to loose. Thank goodness A MINOR adjustmemt and all was well.

 

[steved]

As I said before... I would have done it myself if I could have gotten a new nut in time...



I had a 1994 1500... the pinion bearings failed from running a lockright locker in the rear. Took it to a dodge garage and they replaced all the bearings... they reused the original nut and simply locktighted it. The pinion nut backed off within 75 miles of getting it back from the dealer.



I have been gunshy of reusing ANY part such as this since... that incompetence cost me almost $1000 by the time it was all said and done.



The pinion coming loose caused the surface of the new pinion bearings to fracture... I was replacing the bearing just outside the 12k mile warranty period. From that point on, I am very leary of dealers and their shortcuts, not to mention they didn't even follow their own service manual.

 

[WCounts]

Most of the dealers arround here aren't set up or have a machanic trained to set up differentials. They change seals but send them out for anything else. I've seen a dealer change out the whole assembly for a bad pinion bearing under warranty.

I had a 2002 Z28 that the pinion seal started leaking under warranty. Took it to the dealer and they some how damaged the housing changing out the seal. It was leaking worse when I left so I took it back a week later. They told me it had a bad housing and ordered a new one. I picked up the car two weeks later and you never heard such a loud rear end. They tried to sugest the Z28 rear end were noisy and to drive it. Well it got louder and started leaking again so back it went. The dealer told me to take it back to the dealer I bought it from. I had bought the car out of town. I found out later that the dealer had no dial indicators or a mechanic trained to set up differentials. The dealer I bought the car from didn't do rear ends either, pulled it and sent it out with the new parts. Finally getting it fixed.

The local Dodge dealer I use has trained mechanics and is equiped to do differentials or about anything else.

 

[Coalsmoke]

As I said before... I would have done it myself if I could have gotten a new nut in time...



I had a 1994 1500... the pinion bearings failed from running a lockright locker in the rear. Took it to a dodge garage and they replaced all the bearings... they reused the original nut and simply locktighted it. The pinion nut backed off within 75 miles of getting it back from the dealer.



I have been gunshy of reusing ANY part such as this since... that incompetence cost me almost $1000 by the time it was all said and done.



The pinion coming loose caused the surface of the new pinion bearings to fracture... I was replacing the bearing just outside the 12k mile warranty period. From that point on, I am very leary of dealers and their shortcuts, not to mention they didn't even follow their own service manual.

If that nut backed off with loc-tite, then the threading surfaces weren't properly cleaned first. I spray them down with a bit of brake clean, wipe it off and red loc-tite. Haven't had one move yet.



I feel that so long as a person is only going so far as the pinion seal and as such doesn't need to re-shim, then using an impact to put on the pinion nut to 1/16 - 1/8 of a turn past the original setting is an acceptable practice, as long as you don't screw up and go too far. That is how I do it, haven't lost a rear yet.



Now, that said, when it comes to properly setting up a rear end, you can't just expect to go by feel unless perhaps you are in a shop doing 3 per day. I haven't seen someone in person that good yet, and I definitely know I'm not that good. Figuring how many shims will be needed for the proper pinion depth to get a good pattern is pretty darn important, as is setting proper pre-load and backlash and even with the above accounted for, some people forget to check the pattern on both the drive and coast sides of the gear.

 

[steved]

I've done probably a dozen or so rears ranging from SFs to FFs... never had one die from doing things by feel, and some have a lot of miles on them... never even had one whine.



I set my first rear (that 9. 25 Corp) using all the fancy tools, only to find they were really not needed... at that time, I couldn't afford to pay someone to rebuild it again, so I did it myself (using a new pinion nut). That's when I learned, its not rocket science.



Well, it got done... the original seal did not show any reason for leaking (no nicks or tears)... it may have simply been worn out. The original was a completely different animal than the one I just bought. The original was a single lipped seal, with an extra flap for dirt. The new seal had what appeared to be three separate sealing lips, plus a dirt shield... much stouter design. I forgot to look at the part number to see if its an AA or Ax version.

 

[steved]

Hmmm, its leaking again... new seal, new nut, and now new leak.

The place is going to redo it for nothing, but I'm concerned why (and so are they). This seems to be the first one they've had come back. He indicated that the seal may have been defective, the sealing surface may be bad, or that the seal might have gotten nicked.

I sorta headed off the sealing surface with a retort of "you would have noticed that, I hope?" He agrees...

The worst part of this is that it happens after I tow my 5vr... which weighs 5k. First time it leaked I towed it to my parents (600 miles), now this time was after a 400 mile trip. I know that should have nothing to do with it... just too coincidental.

 

[DPKetchum]

No such thing as defective seals and gaskets. At least I heard THAT for years and the auto manufactures don't pay for seals and gaskets twice. One of the very few things they won't under warranty(back to back repairs such as yours) I thought I had read about a fair amount of these leaking repeatably and it took a new yoke as well as a seal. Got a friend with a clean,well maintained 05 dually 4x4 with about 150k that after about 115k has had front and back replaced like 2 times each. so he's on his third ones. He's not driving that truck much so can't say about this set. But if it leaks again its more then a seal for sure.