Posted by BIG BLUE on July 14, 01 at 17:04:16:
In Reply to: Diagnosing Sounds/signs of imminent rear end failure posted by JJ on July 13, 01 at 14:31:55:
JJ,
Thanks for taking the time to write-up the info regarding the rear end failure. Believe me, I do know what burnt gear oil smells like. My 88 Sub blew a rear gear and when I pulled the pumpkin cover it smelled in the garage for 2 weeks! It's a hard smell to describe but once you've smelled it you always know. I run synthetic gear oil in the 3 trucks we own and so far so good. Thanks again for the details, just wanted to hear someone else describe what it sounds/acts like from start to finish :(
Good luck with the General,
BIG BLUE
: Thanks for your response BIG BLUE.
: I am sure I will be in a fight with Chevy and GM for a while over this one.
: www.ring-pinion.com/Tech%20Library/diagnosing.htm
: check out the above link for diagnosing sounds, excellent info
: The signs of rear-end failure are very very obvious, now that I have experienced it 3 times in a week. The first thing I heard was a very faint howling noise, especially when decelerating, the point on the gas pedal just prior to letting completely off the gas but not accelerating. When the driveline was under steady gas, straight and level, steady speed it was fine. As I began climbing and going down hills, that is when it progressively got worse and quite rapidly. The next sign is the now unmistakeably odor that is associated with a gear burning. I am telliny you there is nothing like that smell. My buddy who was driving behind me was getting noxious, skin burning, headache. It smells like tar burning, kind of like when a new roof is being put on a house. Then as the howling progresses, a grinding and roaring sound chimes in almost like a train roaring by on the tracks blowing it's horn. Then at the very end, if the gear oil doesn't pour out onto the exhaust creating white smoke like your on fire, forward motion ceases with the loudest grinding noise you have ever heard and the truck shakes like the bottom just fell out. That was the first time. The second time was the noise, smell, and smoke, the truck continued to proceed for a few miles. The third time involved the smell and the inital whining noise with some slipping when starting from a stop. After the first time of totally strippng the gears out and having to have the truck towed, I quickly learned not to advance the problem that far and was able to get the truck to dealers under it's own power. I also learned that a HUGE problem that can happen is the rear-end will just totally lock and you will go into a skid as the wheel rears stop turning at 60 mph. That, fortunately did not happen to me, but I can imagine that would be a double E ride.
: Take Care All, service the differential regularly is very good advice. Prior to this I never even gave the diff a second thought. This is something most people never experience in a lifetime.
: Oh, my trany had already burned up a few months ago and I had that rebuilt as well, but with no complications, so far.
: I am curious to hear what "symptoms" you experienced with all 3 rears going out. What were the telltale signs? What did it sound like? Did it just quit altogether or did you start blowing seals or what? We all hear of bad tranny's and rear ends in these trucks but many don't post on the exact nature of the signs before it happens or while it's happening, these are the types of posts that can help the rest of us with a ticking time bomb to defuse the problem before total failure. Let us know, and good luck getting the truck back home.
: : Regards,
: : BIG BLUE
: :
: : : While vacationing into the North Carolina Mountains, pulling a 24 foot travel trailer with a 94 suburban, rear end gave out stranding vehicle in Sylva NC. Dealershp there, rebuilt rear end at a moderate cost of $1400. Oh well, vehicle had 100,000 miles on it. Rear ends always go around then anyway. It gets better. The new rear burned up in 200 miles, stranding family in Buford Georgia for 3 days. Another $1400 dollars because 2nd dealer claimed workmanship error in North Carolina, not covered under warranty. Guess what, stranded again in Valdosta Georgia, another 300 miles, rear blown out. Vehicle towed back to Buford, North of Atlanta, camper stranded in Valdosta. I rented a car and drove back to Ft Lauderdale, Fl, truck and camper left in Ga. Oh, did I mention I also blew a heater core in Macon, Ga and a leaf spring and tire on the trailer in Sycamore Ga. Still in litigation with GM.