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New guy here, broke my 10 bolt rear in first 6 days of ownership... recommendations?

Austin4130

Austin4130

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Title pretty much says it all. Not new to 4 wheel drives/cars, but new to Blazers and 10 bolts. Been into AR-15's, fast electric golf carts, and campain't forums... but out to dive into Blazers.

1991 k5, 6" lift, stock 350 tbi

For now I'm going to go back to the 10 bolt before doing my research and moving onto 3/4 or 1 ton axles... do you have a recommendation for a locker, and replacement 3.73 ring gear and pinion for the rear?

I don't mind giving the business to a forum sponsor. Anybody to stear clear of?

85% street, 5% sand, 10% mud on mud grapplers 35's, don't want to regear the front just yet.

ANY help would be greatly appreciated !
 
Waste of money to stay with 3.73 gears and 35" tires, unless you feel like paying to rebuild a TH700R4 as well.

Martin
 
At the bare minimum find a used pair with 4.10s, shouldn't cost you more than $150 assuming they're both complete. Gives you a chance to go through them and replace the (extremely cheap) wear parts off the vehicle and gets you to what I would consider the lowest acceptable gear for a 700r4 with 35s.

10 bolts sell for scrap value generally. I've had trouble giving them away.
 
Sold the 10bolts out of mine for $100 or so. I'm with Bent on this one. Don't waste money on another 10 bolt rear. The 14bolt SF axle is better alternative to even the 12 bolt.

Or you can take the MAW approch and just get a 4.10 geared 14b full floater. Then all you need to do is regear the 10b front axle, add 8 lug rotors and buy 8 lug wheels. In the long run if you stick with your Blazer for a while, you are going to go for the full floater anyway. I'm not saying get a D60 front axle as it's really not needed in your case.
 
I'm in Houston and have the 10 bolt from mine that you can have. I took the drum brakes apart to get the e-brake cable out, so you'll have to put those back together, but I think I have all the parts in a box. Pretty certain it is 3.73. I'll see if I can figure that out this afternoon. If you are seriously considering doing a new r&p and a locker in the rear, and you plan on paying someone to do the gear set up, I'd just start looking for d60/14ff combo. You have to swap wheels at that point which is an added expense, but you should be able to find a set that has 4.10 or 4.56 gears which are a huge improvement over 3.73 since you are running 35s. It was a very noticeable difference on mine.
 
You are going to burn up your transmission with such high gears, and oversized tires.

Martin
 
Thanks for all of the help everyone.

Upon further inspection, the gear ratio code in the glovebox says GU6, which leads me to believe that these may actually have 3.42 gears...

I bought the truck with the lift and tires already on it... starting to think that the guy (supposedly specialized in Blazers) didn't know what the hell he was doing. Right now I'm just trying to get it back together to get the wife to cool down, (she hadn't even ridden in it before it broke) and go from there.

On another note... there seems to be a lot of the tailshaft (shinier than the rest) from the transfer case sticking out because of the lift... how much is too much?
 
Doesn't matter what the glove box says the gears are, you need to check the gears themself to make sure they haven't been changed already.
How was the lift done? (blocks, all spring, shackle flip?). What other mods were done to the steering to correct it? I'm guessing whoever put the lift on did it the cheap way and didn't do everything that needs to be done, especially when going over 4". This is probably why he sold it, didn't have the funds or knowledge of how to make it correct.
 
Rampage beat me to it, always visually inspect the gears on a used rig to verify your ratio. In case you didn't know, the factory made the 9.5" with 6 lugs if you want to stay 6 lug. A housing from a 3/4 ton square body is a straight swap.
 
Welcome to the site.

A 6" lift is already looking at new driveshafts. A 4" lift is still pushing it in some cases but can be left alone if enough driveshaft is still in the slip part of the case.

A couple of pics could help determine what needs to be done to make it drivable and safe. :popcorn:
 
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