Small oil leak front differential

temco

Original poster
Member
Dec 2, 2013
6
Hello,
I have a 2005 Envoy SLT 4.6L 95,000 miles

At about 80,000 I changed the front differential fluid. About a month ago I noticed a small amount of the oil on the garage floor. A couple quarter size drops...

I got underneath and it looks like its wet around the area where the small drive-train goes into the trans. (I'm referring to the small drive-train that goes from the trans to the transfer case). Sorry I'm not up on my actual part descriptions.

Everywhere else on this vehicle is completely dry. I really despise oils leaks!
Can anyone give some advise? I've searched and all I can find is cv seals going into the differential on the side, transfer case seals, boots...etc
These areas are all good and clean with no oil.

Thanks Tom
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
Welcome! That's the pinion end seal. I would live with small leaks, since replacing that one involves more gear backlash work than the average DIYer can easily perform. You can pull the driveshaft and perhaps put in a new seal without disturbing the setup, but personally, I'd diaper it and ignore unless it got a lot worse.Things (like The Roadie and his truck) often start drooling as they get old.

I think I've only read of 2-3 members on three sites ever doing that exact job and posting about it.
 

temco

Original poster
Member
Dec 2, 2013
6
Thanks for the help!
Pinion end seal huh? Okay, I'll do some research. Must not be a big issue out there.
If my friendly neighborhood mech did it for me, any idea of $$?

Wooluf 1952, good catch on the 4.6. I had 6 cylinder on the brain.

Tom
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
I have a personal policy of not guessing on what mechanics charge, because competence and honesty and local labor rates vary so much. If I guess low, and you don't budget for it, you hate me. If I guess high and you don't do the job and it would have been less, you hate me. I hate to be hated. :redface:

No substitute for calling around. If they check book rates on their computer, even if they haven't done the job before, you'll get a good ballpark. Good ol' boy shops without computerized quote systems might be cheaper, at the risk of them learning on your dime.

Whatever it is, it's NOTHING like the ten hours that replacing the differential would be, due to its horrible location and mounting.
 

temco

Original poster
Member
Dec 2, 2013
6
Thank you Roadie.
I'll call around once I know 100% where the leak is coming from.
I dried up the wet area so I can really watch this closely for the next week or so. I dropped the large plastic oil pan cover for easier access. (Its tight up in there)

I see you have a 2004, has it been good to you? Is there anything else I can do on my 2005 approaching 100,000 that I haven't done already.?

*All fluids including Transfer case have been done less than 20,000 ago. Dexcool changed when I had to put
a new thermostat in about 2 years ago. (Still looks clean) Water pump was changed under warranty.

*I had to change a Mode Door actuator last winter. That was tough, but I managed to get it with the help of a message board.
Very tight up in there. Luckily I'm a thin guy and I was able to hang upside down in the drivers seat, if you know what I mean!

So I guess I'm looking for anything that's most likely to fail that I can head off and do myself now. It's my wife's vehicle and
I'd hate to see her broke down in the future.

Tom
 

RayGumm

Member
Apr 16, 2014
630
Check to make sure the spare tire comes down BEFORE you (she) needs it on the side of a busy highway. Then while it's down, either grind off the 'teeth' on the safety catch thingy or just load it up with a ton of grease or lubricant of some kind to prevent it from sticking and not allowing the tire down.
 
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temco

Original poster
Member
Dec 2, 2013
6
Whoa, good point. This vehicle is coming up on its 10th Ohio winter. Most likely will be stuck as I'm almost positive its never been lowered.
I'll put it on the to-do list. Thanks Ray.
 

triz

Member
Apr 22, 2013
746
I think somewhere in the area of 115-140 was what I paid. Had the first one done by the dealer, second type a local shop.
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
Definitely plugs at 100K. Some owners also do the upstream O2 sensor at the same time. Did you do the brakes and power steering fluids in your "all fluids" project?

I break a lot of things, but I've never had a transmission blow or the usual disasters like that. Check the links in my signature for where I take it offroad.
 

temco

Original poster
Member
Dec 2, 2013
6
Triz, 115-140 sounds reasonable to me. You said replaced twice? At what mileage intervals did the pinion seal leak?

Roadie, I should have mentioned non-fluid maintenance. I changed plugs early 2014. Brakes all around and front rotors
about 2 years ago. No, to the power steering fluid. I've never changed that in any of my vehicles. Should I look into that?
I've never changed an O2...not sure of the difficulty level there.

Spectacular pictures! You're running your Envoy all over creation and I worry about a few Ohio pot holes? haha...
You really show us that the Envoy's are tested tough.

thanks,Tom
 
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triz

Member
Apr 22, 2013
746
temco said:
Triz, 115-140 sounds reasonable to me. You said replaced twice? At what mileage intervals did the pinion seal leak?

Roadie, I should have mentioned non-fluid maintenance. I changed plugs early 2014. Brakes all around and front rotors
about 2 years ago. No, to the power steering fluid. I've never changed that in any of my vehicles. Should I look into that?
I've never changed an O2...not sure of the difficulty level there.

Spectacular pictures! You're running your Envoy all over creation and I worry about a few Ohio pot holes? haha...
You really show us that the Envoy's are tested tough.

thanks,Tom
I would have to check my records but I'm figuring it was somewhere around 50k and 100k miles. The current one has about 40k miles on it so far.
 

temco

Original poster
Member
Dec 2, 2013
6
Triz,
Stopped in my local repair guy's shop yesterday (my wife had the Envoy).
I explained the issue... he knew right away what I was talking about.
He quoted me about 100 to 125.

I'm going to take it in next Wed.

Thanks for your input, definitely appreciated!

Tom
 

Lckent48

Member
Dec 4, 2011
43
I had the same thing. From what I understand it was caused by the pinion bearing going bad & overheating the seal. Ended up replacing all bearings & seals in the front differential, luckily all under warranty. Total cost just under $2,000 at dealer. Not sure if replacing all this was really necessary, but it was a third-party warranty I insisted on when I bought the TB a year ago, and the dealer got them to pay for it.
 

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