I need a straight answer

[cochino12]

I have been doing some checking into what size tire/gear/axle to use on my k5 and am no further ahead then when I started. I will be running a 35" tire 99% street use and on a very rare occasion hittin some mud but nothing crazy. How well will a stock 10 bolt hold up to the larger tires? This is not a trail rig just a DD that I want to sit higher than stock. I have done a lot of research on ck5.com but seems that most people are hard core wheelers and thats it. I have a th350 and am thinking 4:11 or 4:56 gears. Anyone have some experience or more than just a guess how dependable it will be?

[Destructo]

Put some Superior axle shafts in it for 202 dollars for both sides and never worry about the shafts.

I think it will be fine, but theres really no definite answer, axles are not all created equally, so you never really know, but if your axle is in good shape I would say you will be fine, just don't use the gas pedal too much if you get in a situation where the tires may be bound up.

[1FaastC10]

keep it under 35 x 12.50, and you should be fine. 4.10s would be the way to go.

[Chris_T]

I run 35's on my '72 with 4.56 and a 700R4. With the OD I'd really prefer 5.13s. A 4.10 would be a good all around choice, but when I ride in my friend's '79 with 4.10s and 35's it seems a bit sluggish to me. Part of that will be due to the higher 1st gear in the TH350, but part also to the gearset.

If you are not going to do a lot of freeway speeds in your Blazer I'd consider the 4.56's - I think you'll like the quick response. If you will be doing a lot of freeway cruising then 4.10 would be a good choice.

A well maintained 10 bolt should hold up to the 35's. The only problem I might see is if it has a gov-lock. The heavier tires put more stress on it when it engages and they are prone to failure, especially if you have a heavy right foot. It's generally held that the carrier on the 10 bolt is it's weak point.

I'm one of the less hard core CK5ers; I'm not going to sink a ton of $$$ into 1 ton axles any time soon though I'm starting to push the limits of the locked D44 and 12 bolt. There's a lot of good tech there, but you have to wade through the responses from the folks that figure the only way to build a truck is with Dana 60's and 14 bolts.

[Deltaskier]

I think 35's would be ok. You might go through wheel bearings a little faster than normal.

As far as rpm's, this is the best rpm calculator I've found: http://www.florida4x4.com/tech/gearcalc.php

[Jeepster376]

Wow, that's a great calculator. Only thing is it doesn't account for torque converter slip on a non lockup automatic. My cruise RPMs run about 300 higher than the calculator indicates, due to the torque converter slip.

[1FaastC10]

Originally posted by Jeepster376
Wow, that's a great calculator. Only thing is it doesn't account for torque converter slip on a non lockup automatic. My cruise RPMs run about 300 higher than the calculator indicates, due to the torque converter slip.

could also be due to actual tire size. as we all know, tires wear, at different rates, and no two tires are EXACTLY the same size.

[cochino12]

Thanks for he input guys. I think I am going to stick with the 10 bolt and will definitlly do the superior axle shafts. I appreciate it

[Jeepster376]

Originally posted by 1FaastC10


could also be due to actual tire size. as we all know, tires wear, at different rates, and no two tires are EXACTLY the same size.

Cmon, I know my tire diameters, and they're brand new. Torque converters slip, that's what they do. I'm only commenting that slippage needs to be considered. In my cherokee I can lock and unlock the converter on the highway, and see nearly a 500 RPM difference.

[1FaastC10]

you know the EXACT measurement of EVERY tire, at any given time? i dont think so, its not humanly possible. brand new doesnt mean anything, as any 2 tires that come off of the same production line can be different sizes.