Front pinion seal
10-29-2007 | 12:15 PM
#31
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Joined: Feb 2006
Posts: 419
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From: Concord, CA
Something interesting to note though is I ran my truck in 4wd this weekend. As of today, the leak has stopped. I'm still going to change it but it's not leaking anymore. I know.....I checked the fluid in the diff and it is fine.
I was just wondering if the fluid wasn't getting high enough in the pinion housing to "wet" the seal so it dried and shrunk. So, I tried to put it in 4wd and run it good to see. It stopped leaking like I said but I still don't know why.
I was just wondering if the fluid wasn't getting high enough in the pinion housing to "wet" the seal so it dried and shrunk. So, I tried to put it in 4wd and run it good to see. It stopped leaking like I said but I still don't know why.Pinion seals only fail from a Loose part, bad shaft (ie out of balance) or poor setup.
I would bet the seal is just not getting enough splash on it to lube and keep it cool.
I wonder if running a quat over full would help.
10-29-2007 | 03:17 PM
#32
Banned
Joined: May 2006
Posts: 3,660
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From: Florida
But don't the gears and driveshaft still turn just the same in 2wd?
10-29-2007 | 07:40 PM
#33
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Joined: Sep 2003
Posts: 775
Likes: 0
From: High River, Alberta, Canada
One cause I have seen of seal failures is the installation method. The seal should be lubed with a grease (the rubber section) at time of install or they can dry up worse and cause premature seeping. I know, everyone is going to say that the seal gets lubed by the gear oil.... right and wrong. The area in contact with the shaft gets some lube but the other areas behind the shaft don't and they usually still contact the shaft just not with the same sealing force. Overtime the dry contact can wear away at the seal. If one coats the seal with a good layer of multi purpose grease when they install it the seal usually last longer.
This may not be the for sure cause of the seal failures but I suspect it may contribute to the issue. I haven't removed mine yet to see what or if any grease was used at the factory on the seal.
This may not be the for sure cause of the seal failures but I suspect it may contribute to the issue. I haven't removed mine yet to see what or if any grease was used at the factory on the seal.
10-30-2007 | 02:00 PM
#34
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Joined: Jan 2007
Posts: 824
Likes: 1
From: Calgary
My front went and was repared by the 1st POS dealer. Failure came 30k Km later to the tune of a $1000 for a complete bearing pack. No noticable symptoms except for a sudden but small vibration, constant at all speeds. The 2nd dealer, who has proven to be straight and reliable, repaired it and stated that whoever fixed it first left the nut too loose or too tight. I'd be careful doing your own without the torque spec.
The clincher, Dodge wouldn't repair because it was faulty work (by their dealer, the 1st) and not a warranty item. I actually understand their view but it still sucks. I had the 2nd fix it on my tab rather than go back to the 1st and have it fail again anyway after the warranty.
Out of 5 dealers, I found one an hour away that shoots straight. What a PITA.
Cya
The clincher, Dodge wouldn't repair because it was faulty work (by their dealer, the 1st) and not a warranty item. I actually understand their view but it still sucks. I had the 2nd fix it on my tab rather than go back to the 1st and have it fail again anyway after the warranty.
Out of 5 dealers, I found one an hour away that shoots straight. What a PITA.
Cya
10-30-2007 | 07:31 PM
#35
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Joined: Sep 2003
Posts: 775
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From: High River, Alberta, Canada
I have already said it but I will say it again. There is no torque spec for how tight to tighten the nut. There is a crush sleeve that preloads the bearing. The only torque spec is for rotating torque of the pinion flange. The spec states that after reassembly the rotating torque spec should be 3-5"/lbs greater than before it was taken apart.
Copied from the S/M:
REMOVAL
1. Mark the propeller shaft and pinion flange (1) for
installation reference.
2. Remove propeller shaft.
3. Remove hub bearings and axle shafts.
4. Rotate pinion gear three or four times.
5. Measure and record the torque necessary to rotate
the pinion gear with an inch pound torque wrench
6. Hold pinion flange (1) with Flange Wrench 8979 (2)
and remove pinion flange nut and washer
Remove pinion flange (1) with Pinion Flange Puller
8992 (2).
8. Remove pinion shaft seal
INSTALLATION
1. Install new pinion seal with Installer 8882 (2) and
Handle C-4171 (1).
2. Apply a light coat of teflon thread 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 flange with Flange Wrench 8979 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 increments, 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 and hub bearings.
10. Install propeller shaft with reference marks aligned
Copied from the S/M:
REMOVAL
1. Mark the propeller shaft and pinion flange (1) for
installation reference.
2. Remove propeller shaft.
3. Remove hub bearings and axle shafts.
4. Rotate pinion gear three or four times.
5. Measure and record the torque necessary to rotate
the pinion gear with an inch pound torque wrench
6. Hold pinion flange (1) with Flange Wrench 8979 (2)
and remove pinion flange nut and washer
Remove pinion flange (1) with Pinion Flange Puller
8992 (2).
8. Remove pinion shaft seal
INSTALLATION
1. Install new pinion seal with Installer 8882 (2) and
Handle C-4171 (1).
2. Apply a light coat of teflon thread 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 flange with Flange Wrench 8979 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 increments, 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 and hub bearings.
10. Install propeller shaft with reference marks aligned
10-30-2007 | 09:32 PM
#37
Registered User
Joined: Sep 2003
Posts: 775
Likes: 0
From: High River, Alberta, Canada
That is exactly why I am going to do it myself instead of paying the $100 deductible for a half a$$ job. I wouldn't say it is necessary to pull the axles and bearings however measuring how much thread is sticking out of the nut, marking the nut and pinion shaft, then measuring rotating torque as a back up, put it back together with that same nut depth, marks lined up and if need be a hair tighter to get the additional 3-5"/lbs rotating torque. It is almost impossible to just tighten the nut to a preset torque value because of the crush sleeve design.
10-31-2007 | 06:39 AM
#38
Registered User
Joined: Mar 2004
Posts: 367
Likes: 0
From: Denver
I took mine in on Monday and had it back that afternoon. Much to my surprise my dealer replaced the seal and also the yoke. He said the tech. thought there was a burr or rough spot on the yoke.
Then expecting to pay the $100 deductible under the extended warranty plus the cost of new fluid and misc. He told me they took care of it under warranty and there was no charge.
This is with 38.5K miles. I guess that's why they are a "Five Star" dealer. (This is the dealer I bought the truck from)
So far It runs smooth and isn't leaking. Also, I did run it in 4wd for a bit.
I'll keep an eye on it.
Then expecting to pay the $100 deductible under the extended warranty plus the cost of new fluid and misc. He told me they took care of it under warranty and there was no charge.
This is with 38.5K miles. I guess that's why they are a "Five Star" dealer. (This is the dealer I bought the truck from)So far It runs smooth and isn't leaking. Also, I did run it in 4wd for a bit.
I'll keep an eye on it.
10-31-2007 | 08:27 AM
#39
Registered User
Joined: Jul 2005
Posts: 55
Likes: 0
From: Idaho
A local dealer 'fixed' it with new bearings and such. We shall see if it holds. What made me mad at them was that this second dealer left the rear diff plug loose and I happened to catch it leaking before the plug fell out. Why were they back there? We all knew it was the front one that had the problem.
It sucks having a warranty (or not having one as it turns out!).
Dan
11-05-2007 | 10:27 PM
#40
Registered User
Joined: Mar 2004
Posts: 367
Likes: 0
From: Denver
Good thinking on using rubber. I was thinking flexible plastic sheet, but rubber would be better. It needs to be something pliable and something that, if it ever got tangled up in the driveshaft it would easily shred apart and not damage the driveshaft in any way. I'll start looking for something to fab us as soon as I get a chance.
11-05-2007 | 10:30 PM
#41
Registered User
Joined: Mar 2004
Posts: 367
Likes: 0
From: Denver
Mine must have one of those cases that didn't follow the norm. Mine had no signs until I put it in 4WD and terrible crunching noises from the front diff occurred.
There are a lot of occurrences here of leaky front pinion seals. Looking at the pinion seal area, there is an outer cup-shaped metal ring between the pinion shaft and the diff housing that appears to serve as protection for the front seal. The protective "cup" has its bowl facing towards the diff case. For a rear diff, this makes complete sense as the outside of the cup deflects sand/dirt/debris. There is a small gap between the lip of the cup and the diff case--enough space for debris to enter through. So on the front diff, the cup is facing backwards, so now the cup acts like a scoop, catching all the sand/dirt/debris bouncing up off the road and right into the cup where it can get ingested by the seal, causing the seal to leak and eventually fail. This is my hypothesis, anyway. I'm going to look at this and see if there's any way to fab up a small deflector that could be mounted to the diff to deflect debris away from the pinion seal area. I'm thinking of something cone-shaped, kinda like those cones that the vet puts on a dog's head to keep them from chewing their stitches, that could be fastened around the diff case pinion area with a large hose clamp, zip tie, or something.
There are a lot of occurrences here of leaky front pinion seals. Looking at the pinion seal area, there is an outer cup-shaped metal ring between the pinion shaft and the diff housing that appears to serve as protection for the front seal. The protective "cup" has its bowl facing towards the diff case. For a rear diff, this makes complete sense as the outside of the cup deflects sand/dirt/debris. There is a small gap between the lip of the cup and the diff case--enough space for debris to enter through. So on the front diff, the cup is facing backwards, so now the cup acts like a scoop, catching all the sand/dirt/debris bouncing up off the road and right into the cup where it can get ingested by the seal, causing the seal to leak and eventually fail. This is my hypothesis, anyway. I'm going to look at this and see if there's any way to fab up a small deflector that could be mounted to the diff to deflect debris away from the pinion seal area. I'm thinking of something cone-shaped, kinda like those cones that the vet puts on a dog's head to keep them from chewing their stitches, that could be fastened around the diff case pinion area with a large hose clamp, zip tie, or something.
08-15-2008 | 03:10 PM
#44
Registered User
Joined: Jul 2008
Posts: 341
Likes: 0
From: slidell, la.
I have already said it but I will say it again. There is no torque spec for how tight to tighten the nut. There is a crush sleeve that preloads the bearing. The only torque spec is for rotating torque of the pinion flange. The spec states that after reassembly the rotating torque spec should be 3-5"/lbs greater than before it was taken apart.
Copied from the S/M:
REMOVAL
1. Mark the propeller shaft and pinion flange (1) for
installation reference.
2. Remove propeller shaft.
3. Remove hub bearings and axle shafts.
4. Rotate pinion gear three or four times.
5. Measure and record the torque necessary to rotate
the pinion gear with an inch pound torque wrench
6. Hold pinion flange (1) with Flange Wrench 8979 (2)
and remove pinion flange nut and washer
Remove pinion flange (1) with Pinion Flange Puller
8992 (2).
8. Remove pinion shaft seal
INSTALLATION
1. Install new pinion seal with Installer 8882 (2) and
Handle C-4171 (1).
2. Apply a light coat of teflon thread 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 flange with Flange Wrench 8979 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 increments, 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 and hub bearings.
10. Install propeller shaft with reference marks aligned
Copied from the S/M:
REMOVAL
1. Mark the propeller shaft and pinion flange (1) for
installation reference.
2. Remove propeller shaft.
3. Remove hub bearings and axle shafts.
4. Rotate pinion gear three or four times.
5. Measure and record the torque necessary to rotate
the pinion gear with an inch pound torque wrench
6. Hold pinion flange (1) with Flange Wrench 8979 (2)
and remove pinion flange nut and washer
Remove pinion flange (1) with Pinion Flange Puller
8992 (2).
8. Remove pinion shaft seal
INSTALLATION
1. Install new pinion seal with Installer 8882 (2) and
Handle C-4171 (1).
2. Apply a light coat of teflon thread 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 flange with Flange Wrench 8979 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 increments, 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 and hub bearings.
10. Install propeller shaft with reference marks aligned
08-15-2008 | 08:37 PM
#45
Registered User
Joined: Nov 2003
Posts: 641
Likes: 0
From: Lake Nona, Florida
My 04 started leaking well within the warranty, but I had a 7/70 not 3/36... I'm sure it started before the 3 year mark, not sure if I'd topped 36 at that point or not.