Leaking Front Differential Maybe?

[Denali n DOO]

I'll start to say I still occasionally use the dealer for oil changes due to issues with new engine and it still being under warranty . So my last oil change was November 14th at 149025 kms. After the oil change I notice a drip in the driveway and assume they spilled oil when they changed it.

On the November 28th I noticed the drips had turned into 3 10" diameter stains in the driveway, Thinking maybe the filter or drain plug is loose I go back to the dealer on November 29th at 150573 kms, to find out whats with the oil dripping? They said the cleaned a lot of oil from the under belly pan and everything is fine no issues or leaks. The invoice said "Check oil leaking since oil change: Oil caught in frame. Cleaned area. No sign of leaking from engine". I told him then I didn't understand how the oil could be sitting on that belly pan and all of a sudden 14 days later it drains out. It's not like my driveways slope suddenly increased on November 27th and spilled that oil out. It just didn't make sense.

So here I am today looking at another big 10" stain in the driveway. I go back today and she says were busy and you'll have to wait till Monday. I told her no, what if what ever it is that's leaking drains completely and causes a failure. No she said, it will be fine until Monday. I told her that I wanted someone to verify the engine oil level and the front differential oil level are fine before I was leaving. She got all pissy and left and came back with a 3pm appointment today for me. So if they find it's front differential fluid that's leaking do they have me buy the short n curlys to do the repair today (possible seal I would guess), or can I simply ask them to fill up the front differential and then I can deal with it on Monday somewhere else.

I have also noticed this week something is banging around loose when front passenger tire hits bumps.

Any advice before my 3pm appointment.

 

[HARDTRAILZ]

Do not have them do anything but check...as long as that is free. Is pretty simple to check yourself or top off.

I would be worried that they will WANT to find something expensive to blame it on and tell you that it must be fixed since you obviously pissed off the chick they all think is the nicest person and makes the best cookies and brings them lunch on Fridays....

 

[Sparky]

Banging around on bumps? Sway bar links 9 times out of 10.

 

[Denali n DOO]

Do not have them do anything but check...as long as that is free. Is pretty simple to check yourself or top off.

I would be worried that they will WANT to find something expensive to blame it on and tell you that it must be fixed since you obviously pissed off the chick they all think is the nicest person and makes the best cookies and brings them lunch on Fridays....

Okay, that makes sense. If it's easy to check then I will do it myself today, screw them and her attitude, I don't need the grief today. I just googled a MAY03LT video and it does look easy. I'll go spray some Magic Piss (as Matt calls) it on the fill plug and use my Torch (as Matt calls it) to look in there. I hope the fill plug comes off easy.

Then I'll pull out my Roadie Ramps and get a look underneath for the loose whatever it is, hopefully not axle shaft related. I did notice this morning that the shaft has play in the passenger side disconnect area. I don't know whats excessive so maybe I'll post a video.

Be looking at sway bar end links too, thanks Sparky!

Since I'm not going to the dealer I'll go to the Beer Store instead...

Thanks for the reply, my confidence is renewed

 

[Denali n DOO]

Okay, so today I go to my friends transmission shop so I can get the Envoy up in the air and look for a leak. The Dealer said 2 weeks ago there is no leaking. We can't see where the oil is coming from but it had drops near the back of the engine. We check the oil dip stick and it's over the hash mark. I don't get it, oil is leaking out and the level on the dipstick is more than full :banghead:. Back to the dealer for this I guess.

Pinion seal looks like its sweating but not dripping, I'm almost due for Diff fluids to be changed so I decided to have that done tomorrow along with the pinion seal, said he'll charge me $200 for that.

I also noticed while under there that rotten egg smell near the cat, is that normal or not? Engine was warmed up completely then sat for bout 30 minutes before I noticed the smell.

I think while cruising on the hi way the rpm's seem higher than normal, maybe 2200-2300 doing 80 mph? I'll have to hook up this scanner and try to record some info and see exactly what its doing.

 

[Denali n DOO]

Went back today and changed both differential fluids and the pinion seal. The magnet in the the rear had a silver sludge on it but no chunks. Looks good inside. Now this service is behind me at 151,000 km. Now I can rule out the differential for the leak. I'll be watching over the next few days for engine oil drops.. Here's a couple pics of the rear gears.

Another guy I know had his 07 Silverado 1500 hd in there. It's a 6 L and he put a supercharger on it. He was having a new methanol pump installed. When the boost hits 5 lb a green light on the dash turns on the methanol starts to flow, to cool it down I think he said. He has Gibson headers and a Chrome Flowmaster 2 into 1 muffler. Original drive shaft was a 2 piece (crew cab w 6.6 box), he ended up getting a 1 piece aluminum shaft in there. Not sure of the HP but it goes really well. Pics of the supercharger and drive shaft below.

 

[Denali n DOO]

So I took the Envoy to a different dealer today for the Fuel level sensor replacement (50/50 warranty), that's all done and the gauge works properly. The two fingers or whatever you call them were almost non existent.

I also had them check for the oil leak that my original dealer said wasn't a leak, they found the rear engine seal is leaking, it goes back in next week for that. They didn't have time today because the transmission has to be moved back or something to get to the seal, this is being done under my engine warranty.

I can hardly wait to tell my original dealer that the other dealer found what they couldn't. That will be a fun conversation.....IF I go back there.

 

[Old Coot]

I also had them check for the oil leak that my original dealer said wasn't a leak, they found the rear engine seal is leaking, it goes back in next week for that. They didn't have time today because the transmission has to be moved back or something to get to the seal, this is being done under my engine warranty.

I can hardly wait to tell my original dealer that the other dealer found what they couldn't. That will be a fun conversation.....IF I go back there.

It has been thirty plus years since I worked at a GM dealership and I can tell you for a fact, many a dealer will not find a problem covered under warranty if you are not the original owner AND they did not sell you the vehicle! I know, their dealership contract says they have to repair all the GM vehicles, but, when GM pays the dealer for the amount of time it took to install the part in the factory, you can imagine how little the dealer gets to do warranty repairs. They get paid a small fraction of actual costs. So, many dealers

may find the issue, but, it remains unresolved because of standing orders from the boss, unbeknowst to the consumer.

I had a rust through problem with a GM automobile at one time and I was about 15 miles from the rust-through warranty to expire. The local dealer refused to repair it. I asked if the area rep. had seen it yet? Then he had me bring it in so the area rep. could see it, I had to leave it all day as they were not certain when he would be in town. I went to picked the car up that night and the claim was "denied". Knowing that the car would be out of warranty if I drove it. I left it in their parking lot overnight, and would leave it there longer if need be. I called GM when I got home and they said the dealer should repair it under warranty. The next day at lunchtime I went into the dealership and service manager wondered why I had not picked up my vehicle. Our discussion went something like this:

Service Manager: You didn't pick up your car last night, was there a problem?

Me: Yes, I wasn't repaired under warranty.

S.M.: I told you last night it isn't covered under warranty.

Me: Yes, I remember. That is why I left it here so it didn't go over on mileage and that is why it will remain parked here until it is done. When I called Gm they told me you should repair it and if there was any trouble getting it done here I should call the area representative and he would see to it that you live up to your contractual obligation as an authorized GM Dealership. I do have his number would you like to discuss it with him now?

At his point the S.M. became very agitated and became quite vocal, then went into the owners office for 20 minutes for a conference. He came out more composed.

S.M. Take it home and bring it back next week and we will get done.

Me: I have another car I will just leave it here and you can call me when it is done, in the meantime I will contact the area rep. and let him know you will have the car until it is finished to my satisfaction.

Nine days later a new trunk lid with freshly cured matching paint had been installed and a warranty repair receipt placed in my pocket.

I am fairly certain the area rep. never did see the car, he would have told them to fix it and having me bring it in was just a ruse.

 

[Denali n DOO]

Well the Envoys back at the new dealer getting the rear engine oil seal looked after under warranty. I just got the call that it won't be ready until tomorrow morning. Not too bad a deal since they gave me a loaner car this morning to use. I miss the Envoy already since what they gave me is an Orlando...yuck, I hate it , can hardly wait for tomorrow to come....

 

[Denali n DOO]

Oil leak is now fixed. They say the tech believes the oil leak is related to bulletin 05-06-01-034L, I googled that but found no information on it. Tech comments were; replaced crankshaft rear main seal, rear oil seal housing gasket and both front exhaust pipe gaskets. No porosity found on rear cover housing. I don't know what that means?

Would any of the failed parts have contributed to the 2 occurrences of engine oil in coolant reservoir?

 

[Old Coot]

No porosity found on rear cover housing. I don't know what that means?

Would any of the failed parts have contributed to the 2 occurrences of engine oil in coolant reservoir?

It would appear as though they have had some leaks related to porosity in the rear cover housing. That can happen during the casting process. In essence, the casting would have an open cell sponge like structure allowing fluids to move through the material, rather than be a solid non-porous mass.

I have never seen a cut-away view of the engine, but, rear seals do not usually go near coolant jackets in motor castings. My suspicions would be more like a gasket between two mating surfaces that carry coolant and are exposed to lubricating oils, such as head gaskets. Additional possibilites would be oil galley plug leaking into water jacket porous engine casting, engine casting corrosion that pierces the coolant jacket. There are probably more that I can't find in the memory banks right now.

My memory has gotten like a photocopier that is low on toner.

 

[Denali n DOO]

Not having a good morning . I can't believe this truck is gonna let me down again. So here I am, ready to go pick up my sled from the dealer and finally start my riding season, and my truck says NO and fails me again! This morning I looked on the garage floor and saw oil under the truck again . So I go to my friends transmission shop to get a look underneath. No shit, on my way there I get that f'n bump from behind again which has already had a new shaft in it to repair it, now it's back too as of this morning! So we get the truck up and it's leaking oil all over the exact same areas as before. AND.....I notice a few drops of Dexcool as well, now it's also leaking coolant from the water pump gasket. It's booked back at that same new dealer for Tuesday of next week. I hope the water pump gasket repair is covered under the engine warranty.

So then I called GM directly, and politely told them that was not a happy customer, all these engine leaks and oil in coolant leaks. I've had a new engine, new rad, new coolant hoses, flush after flush (one of which I had to pay for because they said I added oil to the coolant). I told her that I think they should give me another new motor as this one keeps having issues. Then she says she gonna start a "customer case" and starts taking all the info. As she looks at the last oil repair on her screen I said, "that's a pretty long list of repairs huh?", and she replies "yes it is, but I have seen worse". I'm suppose to call her back after next weeks appointment. She also asked if I can do a quick e mail to document all my concerns. I want the engine fixed properly before the warranty is done in March.

If not then I want a 3rd motor like Boricua SS

 

[Denali n DOO]

Oh boy, another bad day. So i at the dealer again waiting for oil leak to be fixed. Last time here they changed rear crankshaft seal and housing seal. Today they believe it's coming from the front of the motor and blowing back. They put dye in the oil and are running now and then gonna look with a black light or something. Obviously the rear main wasn't leaking? I'm so disappointed with the service these dealers offer. I drive outta town now to avoid my original dealer and now get more BS service further away from home. Any guesses where it leaking now? I'll update when I find out. Then home to bitch at GM customer service because they want to know the results of today's visit.

 

[Denali n DOO]

WTF, so the dye shows a leak at the oil filter, he says bad oil filter. Do why did they change rear engine seal? I told them to put a new filter on and test again with dye before I leave hear, it's probably not the filter but where it screws in...

 

[Denali n DOO]

So last week I notice leaking fluid again under the Envoy . Looks like coolant but also looks like oil. So I put it up on my Roadie ramps on the weekend for a look and noticed oil leaking again at the back of the engine, also coolant that looks like it came from upper rad hose because it dripped down fan shroud to PS pump and down from there. Coolant reservoir down about an inch from the full mark. Pulled PS dip stick and it looked okay to me.

Took back to dealer today, 5000 km's since last oil change and now at 159770 km's, getting my free oil change from GM due to my issues last time and to also have them look at the leaks again. They advised the engine is leaking at the back again and they will have to separate the engine and tranny to get a look at it and fix it. They also say they pressure tested the cooling system and it holds pressure fine so not leaking, however they say the PS pump is leaking? WTF, so now I have 3 fluids leaking? Now I'm in a stupid white Orlando with GM advertising all over it, I wouldn't even park it in my driveway when I got home. I gotta wait for the call and when I get it I'm going to go back there so they can show me the problems and explain it to me in person. I hate feeling like I'm getting screwed over again and I also hate advertising for a dealership for free with their dealer name all over the sides of the Orlando. Now to call Peggy at GM and give her the update.

 

[Denali n DOO]

The dealer called and the Envoy in done. They said they replaced the rear cover, I'm guessing they did find some porosity on the cover after all. Last time they did this repair they only did the rear seal and gasket and said the cover was fine. Here's the tsb for that job 05-06-01-034L.

Pressure tested coolant system and found no leaks at all. They topped up coolant but couldn't explain why it was down. I'll monitor the coolant level and watch for leaks over the next little while. Oddly enough when googling I did find a tsb 06-06-01-019B that was about mysterious coolant loss due to porosity in the heads. I'm not sure what casting name is on mine tho.

They never mentioned the PS pump this time at all. Yesterday they said it was leaking and I told them it was coolant and just dripped down to the PS pump. PS fluid level was fine on dipstick on weekend when I checked it. But they say coolant not leaking. Time will soon tell what was leaking besides engine oil.

Even tho I didn't get the recall letter they had my info on file and checked my driver door switch. He tells me he has ordered a new one but has to wait for it to come and then he'll do the swap for me.

I hope it really is good to go this time.

 

[Denali n DOO]

Well I just picked it up. Wasn't out of the driveway for 2 minutes and I notice a weird noise under acceleration, tic tic tic tic tic. So I go back and the shop foreman goes for a drive and suspects an exhaust manifold leak , as I'm driving home I think WTF, I'm guessing they had to take the exhaust apart to be able to separate the the engine and tranny. Last time they replaced both exhaust gaskets to do the rear main, i bet they didn't put exhaust together properly , now something else for them to fix...

 

[v7guy]

good lord man, this is quite an ordeal

 

[Denali n DOO]

good lord man, this is quite an ordeal

My Envoy has been an ordeal since the day I picked it up! Three different dealers have all worked on it over the years and all 3 dealers have had dumb shit go wrong, misdiagnosed for several repairs and all sorts of parts thrown at it that it didn't need. Constantly going back to fix what they already fixed. I'm sure most people would have given up on it a long time ago but I keep believing so much has been fixed what else could go wrong? I still have front wheel bearings to change out and something loose on bumps that no one can find. I bet including the new motor my repairs and maintenance cost must be in the $15,000 area, most done under warranty thank goodness...

Ha, you should read my thread on lighting issues, that's an ordeal as well...

 

[Sparky]

Seems the original problem has been blown up to a bigger problem than it should be by incompetent dealers. Geez.

 

[Denali n DOO]

Seems the original problem has been blown up to a bigger problem than it should be by incompetent dealers. Geez.

You ain't kidding about incompetent dealers. So when I did get it home that day I checked the oil level and it was only half way up the cross hatched area after their oil change. They said the cooling system holds pressure so it's fine and can't be leaking, they never even topped off the coolant reservoir after doing the cooling system checks.

So yesterday I get home from my sled trip and I notice another puddle under the Envoy, the wife was driving it, it's f'ing coolant again! I popped the hood this morning and saw the reservoir bottle is now almost empty. No leaks huh? I shine a flashlight down to what I think is the water pump (under the ac pulley on my 5.3) and I see leakage around the two right side bolts. Would a leak there not be detected with the pressure test they did? I just looked up the cooling system part of the engine warranty and it states "Coverage on the engine cooling system begins at the inlet to the water pump and ends with the thermostat housing and/or outlet that attaches to the return hose." So I'm hoping it's covered, not sure if it's the pump itself or a gasket? I'm glad they looked for the leak when it was under warranty because the warranty just expired last week on the 20th. I'm also glad I took the time to keep GM aware of what was going on, that my warranty was soon expiring and the dealer can't diagnose the problem. Now the part I hate is gonna be going back to the incompetent dealer...

 

[jimmyjam]

i had an aftermarket water pump go bad, started leaking at the pulley shaft. started small but after a few weeks was pouring out of there.

under the AC pulley is only the AC belt tensioner. The water pump pulley is what your fan is connected to.

V8 water pump goes for under $200, and bolts on with 4 easily accessible bolts. Its a pretty simple DIY job

**i guess i forgot most people have fan clutches, taking it off is probably the hard part of the job... (its been a while since i've had one)

 

[Sparky]

Honestly if it were me I'd say screw it and do the water pump myself. They've proven their incompetence, don't think I could trust them to do it right, and a water pump isn't that expensive to do. Yeah that fan clutch is annoying but with the right fan clutch tool it unscrews easy enough, and since you have to partially drain the system to remove the pump anyway taking the upper hose off isn't a big deal.

 

[Denali n DOO]

i had an aftermarket water pump go bad, started leaking at the pulley shaft. started small but after a few weeks was pouring out of there.

under the AC pulley is only the AC belt tensioner. The water pump pulley is what your fan is connected to.

V8 water pump goes for under $200, and bolts on with 4 easily accessible bolts. Its a pretty simple DIY job

**i guess i forgot most people have fan clutches, taking it off is probably the hard part of the job... (its been a while since i've had one)

Honestly if it were me I'd say screw it and do the water pump myself. They've proven their incompetence, don't think I could trust them to do it right, and a water pump isn't that expensive to do. Yeah that fan clutch is annoying but with the right fan clutch tool it unscrews easy enough, and since you have to partially drain the system to remove the pump anyway taking the upper hose off isn't a big deal.

I'll look again a little later on and take a few pics and see if you guys can identify what it is I'm looking at and if it could be the source of the leak. So far I've seen coolant on both sides of engine so maybe the pulleys are spraying it all over.

Question, could a water pump leak still allow the system to hold pressure for an hour? While I was waiting for it that day the service advisor told me it held pressure for twenty minutes so it should be good. I told him it was leaking out and the level was dropping. I asked him to continue the test up to and hour (I remembered reading in a members post here that the test should be done for at least an hour) since they were working on the rear oil leak that day, and he said even after the hour it still held pressure.

We all know I'm a noob with repairs but I'm sure if it needs a water pump replaced I can pull it off with help from here but it's hard to not take advantage of free warranty parts. On a side note, I'm a little intimidated with the 2 front hubs I'm gonna replace in the next week or so but I researched the articles and posts and think I can get it done in a day.

 

[TollKeeper]

I would let the dealer repair the water pump. If something fails again, you have a track record of issues that makes GM liable for the repairs.

 

[Denali n DOO]

Well what I thought was coolant leaking at the same time as the oil turns out to be PS fluid flying off the pulley. I had the pump replaced and so far not happy because of the noise, really annoying to say the least. They told me to wait a bit longer and see if it quiets down, could be air. That was at my buddy's shop, not GM.

Anyways back to the engine oil leak that has been fixed twice now, first with a new rear main seal and the second time with a new rear engine cover. Now today I find another puddle under the truck, it's engine oil again....waiting on a call from the GM lady to see what she wanna suggest now. So the dealer that did the work is now closing it's door in the next week or two, so I won't be going back there. I really don't wanna go back to my local dealer with my tail between my legs because I'm coming back after the other dealer failed. I can't believe this oil leak from this new motor is still going on, third time to fix it coming up. And probably at another dealer out of town. I just can't win.

 

[triz]

I will try and get you a pic of what leaked on mine. I also thought it was an engine leak of some sorts. It cost me about 135 dollars to repair. It was the left front axle seal.