• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

Rear End / Smell Update

R

RDSIGN

Charter Member
Full Member
Joined
Jan 28, 2002
Messages
94
Location
Saskatoon, Sask.
Hello all
Last week I was complaining of a natural gas like smell, I traced it to the rearend. Well I just got back from the dealer. They opened up the diff. replaced the oil. they installed a new breather hose and breather fitting. The rearend is not breathing properly and overheating The hose and breather are bigger. The problem for me originated when I was towing a 4000lb trailer into a very strong wind. They had TSB on the problem. I also got a the new designed PCV valve to hopfully stop my oil consumption
 
I noticed a smell from my Avalanche this weekend when I got back into Charleston WV from visiting Knoxville for a conference. When I got home, and dropped the tailgate to get out my bag, I noticed what I would describe a burning rubber smell. Something I will pay more attention to now though.

Hope the PCV valve works. I now have almost two thousand miles since my PCV and lifter change out, and have not noticed any oil consumption.
 
Ha Ha mmdavidw I guess I should watch what I say

ScottInWv I expierienced that smell also.I would pull the filler plug on your rearend I mean diff. and have a smell to see if your oil is burnt

Ron
 
New differential at 7000 miles after a trip to Sturgis and back home - Smelled a natural gas odor from Pennsylvania west and all the way back - 2 days later it was at the dealer for a $2800.00 rear end replacement - complete.

They didn't say anything about a TSB - and I have another trip to Daytona planned next month w/3000# trailer - any info on TSB would be appreciated
 
I know this is an old post, but was all I found when searching.

Pulling our 4800lb+ trailer this past week, I noticed a rotten egg, propane smell, in fact after pulling up a rather long hill, someone who had been driving behind us, asked if we had an open propane tank on the trailer.  The smell was rther strong.

Some other internet searches indicated this could be caused by a rich fuel mixture.

Anyone have any other thoughts?
 
gwh1bass said:
I know this is an old post, but was all I found when searching.

Pulling our 4800lb+ trailer this past week, I noticed a rotten egg, propane smell, in fact after pulling up a rather long hill, someone who had been driving behind us, asked if we had an open propane tank on the trailer.? The smell was rther strong.

Some other internet searches indicated this could be caused by a rich fuel mixture.

Anyone have any other thoughts?
Click to expand...

Nope, but interested in this as well..... I have noticed a strong burnt smell (like burnt rubber) lately from the rear of the Av. I suspect a bad bearing in the rear housing but have not crawled under to check that closely.......
 
The burnt rubber smell is the differential natural fluid odor.  If you can smell it you must have a leak somewhere.  For me it was the right rear passenger axle seal failure that let a little fluid leak out onto the brake rotor casting thus increasing its pungent odor as the rotor heated up.  It was replaced under my extended warranty.  Be sure and wash the area that had the fluid on it after the repair or the smell will linger.
 
We had a local member pull a toy hauler from SoCal to Arizona and we smelled the propane smell as we drove behind him. Then we noticed little puffs of smoke coming from the back of the truck. We stopped him and looked under the truck and saw the whole rear end was glowing bright red. Turns out the reaer end had castings left in it, and disentigrated the insides. He had to have a new rear end put in when he got home.
 
gwh1bass said:
But what about the rotten egg-propane smell?
Click to expand...

any check engine lights?

Rotten egg smell is due to SULPHUR in exhaust which can happen if the engine puter is not getting correct signals and messing up..

but usually it is from bad Cat converter in my experience
 
4MRanch said:
The burnt rubber smell is the differential natural fluid odor.? If you can smell it you must have a leak somewhere.? For me it was the right rear passenger axle seal failure that let a little fluid leak out onto the brake rotor casting thus increasing its pungent odor as the rotor heated up.? It was replaced under my extended warranty.? Be sure and wash the area that had the fluid on it after the repair or the smell will linger.
Click to expand...

Will have to check this since mine seems to comes and go......

Thanks for the info....
 
From a little bit of internet research, too rich of a fuel mixture will cause this propaney type smell from a reaction with the cat convertor.  Now I really need to get into the tuning software to see what is going on.  Anyone remember the name of the book recommended on this site for understanding the workings of the modern day computer controlled engine?
 
ygmn said:
any check engine lights?

Rotten egg smell is due to SULPHUR in exhaust which can happen if the engine puter is not getting correct signals and messing up..

but usually it is from bad Cat converter in my experience
Click to expand...
that was my first thought as well
 
Well, since I don't run cats, we can eliminate that..... (y)

and the book you are looking for is the one I have been recommending for a few weeks on these boards.



http://www.chevyavalanchefanclub.com/cafcna/index.php/topic,55316.280.html

Reply 293..... (y)
 
RDSIGN said:
Hello all
Last week I was complaining of a natural gas like smell, I traced it to the rearend. Well I just got back from the dealer. They opened up the diff. replaced the oil. they installed a new breather hose and breather fitting. The rearend is not breathing properly and overheating The hose and breather are bigger. The problem for me originated when I was towing a 4000lb trailer into a very strong wind. They had  TSB on the problem. I also got a the new designed PCV valve to hopfully stop my oil consumption
Click to expand...

Well I just got back from a weekend of fun with the fam.  We hauled our camper ~3500lbs out to Shenandoah Valley.  No issues on the way out.  Got there unhooked called it a day.  Next 3 days just driving around with no trailer I got the "natural gas" smell in the cabin, but even more so in the box.  Everything was running fine.  Going to take it to the dealer on Wed, a local garage today to see what they come up with.  I have 80k miles on her.  If I toasted the rear end on the only haul I took her on since I owned her I'll be pissed.  I mean this is a relatively light trailer for this truck.  I'll report back and let anyone who is interested know what the verdict was.
 
So I stopped into the local shop on my way out to get my wallet out of the truck.  They couldn't find the smell nor could they duplicate it.  Talking to the mechanic I said "I told (the guy at the counter) to have a look at the rear differential, did you do that?".  He didn't.  Said he would and would call me back later.  Said my diff was a quart low AND it was definitely the source of the smell.  Thats A LOT TO BE LOW!

I had also mentioned that there was a TSB on it (from what RDSIGN stated) and its suppose to get a new breather tube and connection.  They said they called a local dealer after they could not find the TSB themselves, local dealer said that it doesn't apply to my vehicle.  My question is this to you all...WHERE DID THE QUART GO!!  Did it come like that from the factory and I've been driving it around like that for 5 years.  I do baby the truck rarely ever "getting on it", and was only a problem when I hauled the camper and toasted the fluid?  Your not suppose to change your diff fluid till like 150K miles or something silly like that.  I checked for leaks before I brought it in, found none, no fluid on the chassis.  Mechanic told me the breather tube was not clogged nor did it look like any fluid came out of it.  Im stumped.

I'll even give the shop a plug Protime Auto on Haygood Road in VB.  Good buncha guys (and girl).  I dont have the time to do this myself anymore and I trust them.  They always give me the answers I want to hear, let me in the garage when they are doing work and the fact that they went the extra distance and called the dealer about my issue when they couldnt figure it out makes me appreciate em even more.

Let me know what you think, will going in and cleaning the diff and replacing the fluids fix me?
 
You must log in or register to reply here.
Back
Top