redfishsc
Tired of fixing lousy engineering.
Truck--- 1999 Suburban C1500 (2WD), 5.7, 206K miles, worth saving. Engine in excellent shape, clean truck. I take the family on week long camping trips 300 miles from home, so I really want to keep the truck in reliable shape.
Rear end is G80 locker, 3.43 ratio (that I don't like), 10 bolt. 5-lug wheels, drums. Truck actually drives very nicely. You don't feel anything in the drivetrain that says "somethings wrong".
Rear differential has been singing on deceleration, particularly if I'm coasting in lower gear. Sound is NOT chunky/crackling. Instead, it simply sounds like someone has laid a stick of rebar on a spinning driveshaft. Not a sharp squeal, but a dull metal scrubbing sound. There's also "some" noise while moving forward but I cannot tell if it's the diff, or if it's just normal road noise, or just normal drivetrain hum on an old truck.
You mostly hear it with windows down, it's not overly loud. You can only barely hear it with windows up. Been sounding like this for several months, but it was only this past week that I realized it was the differential.
I also hear a "clunk" that happens when I'm pulling up to (or, pulling away from) a stoplight. Maybe it's the slip on the yoke reseating, maybe not, but perhaps it's the pinion that's been loosened?
I have not yet inspected the U-joints, and the drums do not have anything in them scraping.
Two weeks ago I removed the diff's cover. Oil in it was fine, still even slightly clear. Not sure how many miles but it was at least a couple years old. The ring gear looked fine to me. The magnet only had "metal sludge" on the magnet. I don't know what's normal, there were a couple tablespoons of silvery metal sludge on the magnet. NO chunks or shavings. Refilled with Mobil1 gear oil.
My suspicion is that the pinion nut has come loose (for whatever reason, maybe weak crush sleeve?) or the pinion or carrier bearings are going out on me.
Either way, locally I've been quoted $1200 just for a bearing swap (no new gears). Local salvage yards are few here in Charleston, not easy to find a used rear end to swap.
Are there reputable online places? I've considered buying one from Weller, Powertrain, etc but swapping the rear is a HUGE amount of work for me to do myself just to get a reman diff with a poorly calibrated backlash.
I've never had to work on a rear end before, so any advice is appreciated.
If I swap it, I'm likely to go with a 3.73 since I occasionally tow a camper, and my daily commute is only 5 miles. I'm not too fond of the 3.43.
Rear end is G80 locker, 3.43 ratio (that I don't like), 10 bolt. 5-lug wheels, drums. Truck actually drives very nicely. You don't feel anything in the drivetrain that says "somethings wrong".
Rear differential has been singing on deceleration, particularly if I'm coasting in lower gear. Sound is NOT chunky/crackling. Instead, it simply sounds like someone has laid a stick of rebar on a spinning driveshaft. Not a sharp squeal, but a dull metal scrubbing sound. There's also "some" noise while moving forward but I cannot tell if it's the diff, or if it's just normal road noise, or just normal drivetrain hum on an old truck.
You mostly hear it with windows down, it's not overly loud. You can only barely hear it with windows up. Been sounding like this for several months, but it was only this past week that I realized it was the differential.
I also hear a "clunk" that happens when I'm pulling up to (or, pulling away from) a stoplight. Maybe it's the slip on the yoke reseating, maybe not, but perhaps it's the pinion that's been loosened?
I have not yet inspected the U-joints, and the drums do not have anything in them scraping.
Two weeks ago I removed the diff's cover. Oil in it was fine, still even slightly clear. Not sure how many miles but it was at least a couple years old. The ring gear looked fine to me. The magnet only had "metal sludge" on the magnet. I don't know what's normal, there were a couple tablespoons of silvery metal sludge on the magnet. NO chunks or shavings. Refilled with Mobil1 gear oil.
My suspicion is that the pinion nut has come loose (for whatever reason, maybe weak crush sleeve?) or the pinion or carrier bearings are going out on me.
Either way, locally I've been quoted $1200 just for a bearing swap (no new gears). Local salvage yards are few here in Charleston, not easy to find a used rear end to swap.
Are there reputable online places? I've considered buying one from Weller, Powertrain, etc but swapping the rear is a HUGE amount of work for me to do myself just to get a reman diff with a poorly calibrated backlash.
I've never had to work on a rear end before, so any advice is appreciated.
If I swap it, I'm likely to go with a 3.73 since I occasionally tow a camper, and my daily commute is only 5 miles. I'm not too fond of the 3.43.
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