1990 R1500 Suburban blew differential

[romancatholicism]

Carrier broke where the carrier bearing presses onto the nose on the ring gear side yesterday......various people have claimed this is common for the 8.5 10-bolt axle. Has anybody else suffered this?

What sould I do...have entire set up replaced at the tune of $750-800, and possibly even replace the broken open carrier with a posi unit for even more.

Or buy a complete junkyard axle and swap out myself for $200-250 and chance another failure due to high miles.

Any opinions will be helpful.
By the way....I'm very low on cash...Anyone have spare parts laying around?

[rhandwor]

I don't know your qualifications but you can get new bearings pressed on a junk yard unit if bad. As long as the axle shaft is good you shouldn't have problems. Did you break off the end of the main gear or the bearing. If just the bearing broke you should be able to get a new bearing pressed on. If you use the same shims and it isn't noisy you should be alright. I have swapped ring and pinion gears and if you take a dollar bill and run it through the ring and pinion gear it should just make little cuts in the bill otherwise it is either to loose or to tight. The big thing on a junk yard unit is play if you move the axles. For the small gears they sell shim spacers at the dealer to take out play.

[1990 Suburban]

Yeah, I've got a good working knowledge of diff's cause I work at American Axle here in Detroit. Mainly I build the 14 bolt axles and the axles for the H2. I was just having trouble making up my mind as to what avenue to go down. I've decided to have the work done by a place called the Ring and Pinion Shop. I'll get a discount off parts since I'm an AAM employee. Since I'm going the new parts route, I'll have a choice in ratios and whether I want a Eaton locker instead of the stock open-style carrier that broke on me.
My Burb came with an optional 3.73 gearset, but I'm stronly leaning towards selecting a 3.42 for mileage and towings' sake. Normally when I tow the snowmobiles in the winter, I'll use Drive instead of Overdrive for fear of smoking my newly rebuilt 700R4. With the 3.73 gears being spun by Third gear, my highway speeds are greatly limited as are the MPG's.
Does anyone have any opinions or comments as to my ratio choice or what type of Limited Slip Differential is best for durability. I'm aware that there are different style Locker/Posi units out there...governor,rachet,clutch packs and springs...etc. My .040 over 350 has 3500 miles on it now, so it's basically going to be a "new" Burb mechanically.

Thanks for any input given!!!

[1990 Suburban]

To give you a better understanding of where the carrier broke, picture the fact that I was able to remove the carrier w/ring gear with only the pass side saddle cap removed. The race and the tapered carrier bearing(with a piece of the carrier snout inside it) were still bolted under the drivers' side cap!!! The only thing holding it all aligned was the shaft skewered through that break, and into the side gear. Needless to say...more than half the teeth are gone on the ring gear!

[1990 Suburban]

Oops!!.....I guess I'm registered under two different User Names...sorry for any confusion. "romancatholicism=1990 Suburban, 1990 Suburban=romancatholicism"

[sub006]

My differential specialist, who has been doing nothing but building, rebuilding and installing this particular component for decades, advised me to stay with the 3.73's on my 1990 2wd. He said the gas mileage difference is minimal with the 700R4 overdrive.

BTW my factory diff blew at only 85,000 miles. Replaced with an Auburn posi that has gone 320,000 so far (total vehicle miles 405,000). And I get 16-17 mpg highway.

[idmetro]

Budgetary constraints dictated my choice. I just replaced the torn up rear differential in my 86 suburban with a junkyard unit. The replacement looked like it had been opened previously but was smoother than mine had ever been in the 5 years I've had it. We shall see what longevity turns out to be. By the way mine is 4wheel drive with the 3.73 gear set powered by a 350 and I ran 12mpg previously, I'll check to see if there's any difference with the replacement unit.