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Front Differenial Leak

WVBubba

WVBubba

SM 2003
Full Member
Joined
Jul 18, 2002
Messages
3,285
Location
Hurricane, WV
while haveing my AV is shop for burned out seat heaters and noisy heater motor I had them check front & rear differentials....they found a leak in the front differential that I was not aware of, No signs of oil on ground...may want to keep an eye on this...fyi WVBubba
 
I was up under gandolphxxs rig the other day and noticed a leak on his front diff. You might ask him if he had it looked at yet and what he found. BTW gandolphxx if you want to bring it back to my place I would be glad to check it out for ya.
 
This reminds me. Natural differential fluid versus sythnetic differential fluid. I was in the dealership two weeks ago and they were speaking to a customer regarding his front differential. Apparently if you decide to go to synthetic, you need to replace the breather valve. The one we have is.. er.. black, I think. And the one we need is.. white. It's either that or the other way around. Regardless, if you change fluid types, you need to change the valve. If you do not, you risk losing fluid and damaging the differential and GM will _not_ honour a warranty claim if this occurs.

Just my two cents. :)
 
All,,,

I have heard that Synthetic Gear Oil is not compatible with the soft sealant GM uses on the front diffs. (there is no hard gasket used when the sections are mated @ factory) ... If you use Synthetic, it will eventually leak... I have had 5 of these cases, and used Dino, and never a leak... Most of the front diff. leaks mentioned on the GM Sport Utility Perf. Forum were due to changing to Syn...

11H
 
11H said:
I have heard that Synthetic Gear Oil is not compatible with the soft sealant GM uses on the front diffs. (there is no hard gasket used when the sections are mated @ factory) ... If you use Synthetic, it will eventually leak... I have had 5 of these cases, and used Dino, and never a leak... Most of the front diff. leaks mentioned on the GM Sport Utility Perf. Forum were due to changing to Syn.
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I do not know what causes what. I am just reporting what the dealership was discussing. They were reading a technical bulletin from General Motors to the client.
 
11H said:
All,,,

I have heard that Synthetic Gear Oil is not compatible with the soft sealant GM uses on the front diffs. (there is no hard gasket used when the sections are mated @ factory) ... If you use Synthetic, it will eventually leak... I have had 5 of these cases, and used Dino, and never a leak... Most of the front diff. leaks mentioned on the GM Sport Utility Perf. Forum were due to changing to Syn...

11H
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Mea Culpa, forgive me Father, for I have sinned - had Redline put in the front differential when the gears were changed - and now it appears to be leaking :C:

More on this later after I have it further examined :C:
 
Just picked up my Av from the dealer today, they had to check out the rear diff because of a howling noise and replaced the rear diff fluid with synthetic, they never said anything about needing a different breather ???

Will have to call and ask them that tomorrow.
 
SNO SLYD said:
Just picked up my Av from the dealer today, they had to check out the rear diff because of a howling noise and replaced the rear diff fluid with synthetic, they never said anything about needing a different breather ???

Will have to call and ask them that tomorrow.
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The REAR differential fill requires synthetic only. No need to call your dealer. (y) ;D
 
gandolphxx said:
Mea Culpa, forgive me Father, for I have sinned - had Redline put in the front differential when the gears were changed - and now it appears to be leaking :C:
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That might certainly explain your front differential leak. Keep us informed. I am interested in how this progresses and what your dealership has to say. (If they say it is not covered by warranty, just say, "Uh.. well.. good thing I didn't use synthetic then! And by the way, do you have a sale on differential fluid?" Then hurry outside and change it.) ;)
 
Fortunately or unfortunately no dealer will touch the underside of my Beast - warranty went bye bye along time ago, NBD, I prefer to have a known, trusted ASE certified mechanic and shop touch my underside privates. ;D

I am madder at myself, since I provided the dayum fluid for the folks when they did the gear swap.

I will post progress reports as soon as I get my hairshirt pressed.

what I really want to do is get a complete workup of the bottom of the Beast,

1. Both differentials and MagTek on the rearend
2. Tranny flush and check
3. Wheel bearing and lube check
4. New bushings
5. New shocks
6. Better oil filter system

That ought to make it feel better :love:
 
Going with a new set of Rancho 9000's?
 
Steelheadchaser said:
Going with a new set of Rancho 9000's?
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I am debating the Rancho 9000x vs the Edlebrocck IAS - any thoughts welcome ;D

I am also contemplating upping my torsion bars, possibly with the 1500 keys - that should start a firestorm >:D
 
I have no experience with Edelbrock shocks, but I have put Rancho 9000 's on my last 2 4x4s with excellent results. When my Av starts getting a bit too soft, or has a has to much jounce, I'll be buying another set. I'll probably get the remote adjuster gizmo this time. I don't enjoy rolling around the ground under trucks as much as I once did.
 
Steelheadchaser said:
I have no experience with Edelbrock shocks, but I have put Rancho 9000 's on my last 2 4x4s with excellent results. When my Av starts getting a bit too soft, or has a has to much jounce, I'll be buying another set. I'll probably get the remote adjuster gizmo this time. I don't enjoy rolling around the ground under trucks as much as I once did.
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I hear you, feel the pain in my joints too - thats what attracted me to them. >:D
 
Just to poke in here... As far as shocks, my PERSONAL opinion is Bilsteins are probably the best all arounders on a truck ... Plus, they last forever...

To comment on Rancho, I think they used to be the best off road shock on the market, but lately that doesn't seem to be the case... :) I can elaborate if you want...

It seems gandolphxxf, you might want to check out KYB ... You race a lot, and they do well with weight transfer... They are not an optimum off road shock though...

In my opinion, the IAS concept is gimmicky... I have heard of guys using them on trucks and F-Bodies, and went noticed no difference from Bilstein, KYB or Koni ...

Like I said, the best do it all shock I think is the Bilsteins ... They are pricey, but are there to stay ...

Gabriel makes a "road sensing" shock similar to the IAS ...

It it were me and I had a 3/4 ton avy, I would get some nice Bilstein HD shocks, and rear bags for when I needed pre-load...

gandolphxxf, I had no idea 1500 keys were an "upgrade" ... interesting deal... Can you elaborate?

11H
 
I had the Rancho 9000's on my previous truck (93 C3500 dually) with the remote adjustment set up . It made a huge difference in the ride vs. the stock shocks. The 1 ton suspension was rather stiff and when taking corners on bumpy roads the back end would hop and slide over the bumps. I ran the the rear shocks on the softest setting and it completely eliminated that problem. I would buy them again.
 
Looking at Gandolphxx front diff yesterday revealed his is leaking around the plastic insert where the vent comes out. Appears the vent unit is an assembly. I am checking on how this piece is either resealed or replaced. Will report early next week. ;)
 
I have the same problem, on the drivers side. I think its the front pinion seal thats leaking.

My question is if the dealer would have to remove my 3.73 gears in order to repair this problem? I would love to throw some 4.10 in there for free.


-Rob
 
NYCBlueZ71 said:
I have the same problem, on the drivers side. I think its the front pinion seal thats leaking.

My question is if the dealer would have to remove my 3.73 gears in order to repair this problem? I would love to throw some 4.10 in there for free.

-Rob
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I doubt that it would be free. You would have to buy the new ring and pinion set. Plus, the rear has to be changed out as well.
 
My mechanic told me my front differential was leaking also. I took it into Team Chevrolet in Pasadena. The idiot there told me it was because I was using a K&N Oil Filter :7:
Oh please!
Anyway I haven't had time to take it to another dealer yet. :8:
 
Took mine to the dealer for the 9000 miles service checkup, found that the front differential was leaking and the back was low.... didnt say anything about synthetic though!! ???
 
Guys,,,

The synthetic fluid incompatability in the front diff. came out in a TSB from GM quite a while ago... I read it back when I had my '99 New Body Silverado Z-71 ... A lot of guys on the GM sport utility performance board were converting to syn, and had leaks... Then MikeL (a technician) posted the TSB, and it stated nothing but Petroleum 80W-90 should go in the front diff... Syns are not compatible with the soft red sealing compound per GM ...

Hope this clarifies...

11H
 
my problem was similar.....I had a front vent leak. they resealed it.
 
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