axles and regearing

88blazer383 · January 19, 2014

Hi, I'm new to this forum and tried searching for similar posts before I decided to start a new thread. I have a 88 k5 with the 700r4. I also have a 383 stroker pushing 390 hp if that makes a difference. I currently have the stock 10 bolts with the 3.42 gears. My spider gears are destroyed in the rear and before buying anything I decided to seek some advice.

I'd like to regear but I'm not sure of the best ratio. From what I understand, I should have 3.73 or 3.90s for 33" tires. I've considered 4.10s because while I'm unsure of future tire size, I want to keep 35s as an option. I do mostly city driving with the rare and occasional short spurt down the highway.

This brings me to my final question, would it be worth it to put on 1 ton axles before I do all this work? What are the pros and cons?

Thanks in advance

94sierra16 · January 20, 2014

You dont have to put one ton axles up under it unless you want to spend the extra money and make your axles stronger. And i would go with 4.10s because you said you may want 35s down the line. And it would be alot cheaper to put them in instead of lower gears then youd have to switch them out again

Squirrely · January 20, 2014

I run 456 gearing with my 35" tire combo. Tons of off the line snap and towing is easy. Gas mileage takes a small hit, but I don't care.

383 with 35's... check out 427 gears. Not sure if they make them for the 10 bolt. Check out Yukon axles and lockers.

Or, if you could move to a 12 bolt rear that be a good choice, not a requirement.

Squirrely · January 20, 2014

Yes you can snap axles on a 10 bolt with 35" tires. Especially if you run a locker....

88blazer383 · January 21, 2014

After making a lot of phone calls, I found a guy with the 14 bolt six lug out of a 2500 had with 4.10 gears. I'm going to check it out tomorrow and look at the gears and see how easy a swap it would be. Some people say it bolts right on, but I was also told it might require spring perch relocation so I'm not sure yet. I decided to look for this axle because I did hear about the 10 bolt having some issues with larger tires.

I appreciate all the help and will let you know if it works out. If it doesn't, I think I'll go with 4.10s just because I know if I get anything above that I would enjoy burning off tires too much.

88blazer383 · January 24, 2014

So the 6 lug 14 bolt I got is the 2wd version, it's about 3 inches short. I'm fed up with this whole axle situation so I'm about to just rebuild the axle myself even though I have no idea what I'm doing. I have one last option and wanted yalls take on it. It's a Chevy 12 bolt with 4.10 gears. It has a Detroit locker, full float conversion kit and less than 10,000 miles on it. The guy had it on a k5 so I assume it'll bolt right up. Are there any weak points to the 12 bolt, especially with the full float? I know ff is great on the 14 bolt but I have little knowledge about the conversion. Any help is appreciated.

Also, are there any downsides to running a Detroit locker on my dd?

Squirrely · January 26, 2014

If you can get a deal on the 12 bolt then go for it.

And a full floating rear is going to be far stronger than what you have now.

I found this which sums it up nicely.

"The full-floating design is typically used in most 3/4 and 1-ton light trucks, medium duty trucks and heavy-duty trucks, as well as most agricultural applications, such as large tractors and self propelled agricultural machinery. There are a few exceptions, such as many Land-Rover vehicles. A full-floating axle can be identified by a protruding hub to which the axle shaft flange is bolted. These axles can carry more weight than a semi-floating or non-floating axle assembly because the hubs have two bearings riding on a fixed spindle. The axle shafts themselves do not carry any mass; they serve only to transmit torque from the differential to the wheels. Full-floating axle shafts are retained by the aforementioned flange bolted to the hub, while the hub and bearings are retained on the spindle by a large nut. A benefit of a full-floating axle is that if an axle shaft (used to transmit torque or power) breaks, the wheel will not come off."