Oil leak...

[AC75TB07]

Got home two days ago and parked my TB after getting new front bearings installed. There was no oil leaking at the time or I would have seen it while on the garage ramp. Today I start it up to give it a clean out and let it idle while I listen to the radio, and about 10 minutes later I see a small patch under the engine. Seems to have literally appeared out of nowhere. The truck was sorta tipped to the left so the leaking oil was running down that direction and dripping off the frame. Stopped when shut off and cooled down. I can't really see where it's from but wondering where the likly source might be? Any well known suspects? Only 150,000KM (Canada) on the engine so was not really expecting this. Also checked the dipstick but level wasn't low

Just looking for ideas on what I might be dealing with...

Thanks

 

[Redbeard]

Oil pressure sending unit is often culprit on the 4.2l engines. What engine do you have?

 

[AC75TB07]

Yes, it is the 4.2, 2007 LT model. Would I be able to tell if this is the issue by just looking up from underneith while laying on the ground? I dont have a ramp or nothing. Is that an expensive repair for both parts and labour?

Side note. I had the truck running today for about 10 minutes in the driveway but didn't see much of anything dripping so I just... don't know.

 

[mrrsm]

Some things to note for possible places for the GM Atlas Engine to present with Static Oil Leaks:

(1) Loose fitting Oil Drain Plug. (Do NOT Over-Tighten This Plug!)
(2) Front Timing Chain Cover Oil Seal behind the Harmonic Balancer- Serp Pulley.
(3) Rear Engine (Crankshaft) Oil Seal ...Hidden behind the Flex-Plate.
(4) CPAS Solenoid (Passenger Side of Upper Engine Head)
(5) Poorly Installed Oil Filter. (Do NOT tighten more than 1/4" Turn after Snug).
(6) Rear of Valve Cover (Worn Flat "O"Ring Valve Cover Gasket)
(7) Oil Pressure Sending Unit (Adjacent Oil Filter Manifold) Lower Right side of Engine).
(8) Leaking Drive Shaft Take Off Seal.

Things to Do to try and Isolate the Leak(s):

A. Get a LARGE Piece of Cardboard that reaches from the Front of the Atlas Engine to just past the U-Joint at the Tail End of the 4L60E Transmission and mark an Edge Outline of the Left and Right Front Tires for reference later on.

B. Park on the Most Level Available Spot on the Drive Ramp and orient the Dry Cardboard as an "Over-Night Blotter" to show you where MOST of the Oil is Dripping and in What Quantity.

C. Take a Digital Image of the Cardboard in the Morning after you set it in place and post that Image back here.

D. Visit this Link below...and Courtesy @Mooseman ... Download the correct GM OEM Shop Service Manual for your particular Year-Make-Model of SUV and refer to that Digital Document for ALL repairs and Diagnostics:

Need service manuals? Get them here!

********* Please note that the FireFox browser has issues with the password handling and that these downloads are not under HTTPS, flagging them as security risks. Chrome and Edge work fine once you allow the download. ********* ATSG 4L60E Manual 4L60E Rebuild Manual 2005 GMC Envoy XUV...

gmtnation.com

 

[Reprise]

Check your p/s fluid level, too. I just got through replacing my high pressure lines on my pickup; they go out frequently on the 360s, too.

The other thing is, the fluid can look like oil. Get a white paper towel and see if you can get some of the fluid on it to evaluate (or leave it under the truck overnight, etc.) If it's coming from the high pressure hose(s), it'll continue to drip a little after the engine has been shut off. And it'll be on the LH (driver's) side.

 

[AC75TB07]

UPDATE: I do not think it is an oil leak.

I went for a drive today and checked the oil, no leaks to see and the oil level is good. But I did get under the truck and the area around the driver CV joint is soaking with some type of dark fluid... gear oil? transmission fluid?.... The frame below is wet but nothing above that area. There's no noticeable difference in the drive or handling, but I did JUST have the hub bearing replaced on this front side last week. Is it likely to be anything related to that, or some form of seal or the CV joint itself? There is no tear in the CV boot that I saw. What are the possibilities here? Best and worst case sinario? Costs estimates?

 

[mrrsm]

The next time you get under there... Take some clear images of the engine compartment and Suspension (Driver's Side, Front of Engine, Passenger Side and Transmission area) and post those back here... so we can all SEE what you can SEE. :>)

 

[AC75TB07]

Not likely to be able to get that. Tried to get a pic today but it's just too dim without it up on a ramp. And I don't get home until it is nearly dark anyway. Not to mention it's been raining for the past three days.

But basically, everything around the CV area is wet with some type of fluid but otherwise looks as it should. I'm just looking for what you guys would suspect. There's a lot of talk of seal replacement online, but what type of seal is in this CV area? Axel seal?

 

[Blckshdw]

Wondering if your motor mount may have split, and lost its fluid?

 

[Reprise]

Wondering if your motor mount may have split, and lost its fluid?

If that happens, will he notice the motor shaking at idle? (either by feel or visual)

 

[Blckshdw]

When mine went, the difference was minimal, although it's just my passenger side ATM. Have a replacement set in the garage, have put it off, cuz it doesn't bother me (yet)

 

[Reprise]

Yeah, it would prolly have to bother me to the point of 'not running' to get me in the mood to swap those out. Although I could probably buy a hoist for the $$$ I'd save doing it myself.

 

[Mektek]

Is it the inner or outer joint that's wet?
If it's the inner joint then your differential shaft seal may have failed.

 

[AC75TB07]

There is no shake at idle or while driving whatsoever. I recently had two new front bearings replaced and the truck now drives & rides smoother than ever.

As for the fluid being on the inner or outer of the CV, I can't really tell since the entire area is wet or at least has some type of oily residue. That said, the first time I noticed this the truck was leaning to the left and the fluid was dripping quite fast at idle, but since then there seems tobe less fluid on level ground with only a few drops forming and dripping from the frame.

 

[Mooseman]

Give the oily mess a sniff test. Differential gear oil is particularly pungent (and for some people nauseating). If it's diff oil, it should be evident.

 

[TollKeeper]

Dont forget to check your front diff fluid levels too. Thats a miserable diff to have to replace if it does eat a bearing or gear.

 

[Mektek]

Tilted to the left would cause the remaining oil level to increase and drip out the failed seal. Level or to the right would lower the level and slow or stop the dripping.
When I got my TB the diff was almost empty. I refilled it and in a few days I noticed the oil had leaked and sprayed from all around the inner joint. Time for seal replacement

 

[AC75TB07]

I did give it a sniff and it was rather strong. It first leaked on my grass and I grabbed a rubber glove and checked it out. It smelled like oil, but quite strong. Having checked my engine oil, what was on the grass did seem to be darker and sorta thinner.

What Mektec said makes a lot of sense. I'm headed to the garage on friday and expect the seal to be the issue. Hopefully it's not too costly to replace it.

 

[AC75TB07]

Seems like Reprise was the poster with the right answer.... it's my power steering! The lines are leaking heavily and the rack is shot. I did know there was a slight leak that I occasionally had to top up, but not knowing where the lines ran right above the driver side wheel, I didn't know what I was looking for. So, good news is all my axle seals etc. are in great shape, but the P/S repair is gonna cost a small shitload. Oh well...