Keep or sell 14bsf axle set for k10

[hunters628]

Alright guys it’s coming up on decision time and I’m not sure what to do so I’m seeking opinions. I have a 82 k10 short bed that I am currently building a 6.2 turbo diesel for. The truck currently has a Sm465 and stock half ton 3.08 geared axles. I picked up a set of 82 k20 axles a couple months ago and they are geared at 4.10. Rear axle is a 14 bolt semi-float and I’m not sure on the front. I’m pretty torn on what to do here. The truck will be my daily driver and I would like to be able to maintain freeway speeds. It will never tow and the only time it will go off-road is when I drive out to hiking trails. Max tire size I will run will be 33s. So from my point of view to use the 3/4 axles I’ll have to re gear as low as possible or do a NV4500 swap. I’m not sure the price is worth the advantage in strength for my application. I believe my stock rear axle is a 10 bolt with the g80 gov-bomb. So I would at least put a posi or Detroit in the rear if I keep the 1/2 axles. Let me know what you guys think. 33s with 3.08 gears and a Sm465 may be a complete dog with the 6.2, I just don’t have enough knowledge to make the decision on my own.
Thanks guys,
Hunter

 

[bucket]

If you don't want to do an overdrive trans swap, I'd stick with the current 3.08 axles. That 6.2 won't like 4.10's for sure.

Installing a full-carrier type locker or limited slip in the 10 bolt will eliminate one weak area.

You can always install a 6-lug 14sf rear from an '88-'98 truck too if you are worried about strength. But if you really aren't going to tow, haul, of run larger tires, you 'should' be ok.

 

[hunters628]

Forgot to add if I keep the 1/2 axles I get to keep the 15x10 factory steels I have with the hubcaps. If that sways anyone’s opinions.
I’m not against going to a overdrive tranny, but if I can accomplish the same outcome, without sacrificing too much strength, cheaper I’d like to keep what I have. Besides the carrier what is the other main weak points on a 10 bolt? Pinion?
Thanks,
Hunter

 

[78C10BigTen]

Forgot to add if I keep the 1/2 axles I get to keep the 15x10 factory steels I have with the hubcaps. If that sways anyone’s opinions.
I’m not against going to a overdrive tranny, but if I can accomplish the same outcome, without sacrificing too much strength, cheaper I’d like to keep what I have. Besides the carrier what is the other main weak points on a 10 bolt? Pinion?
Thanks,
Hunter

So far im on my second 10 bolt in the rear of my 2wd and both have blown or have a leaking pinion seal. Maybe just me but keep your eyes on it

 

[hunters628]

So far im on my second 10 bolt in the rear of my 2wd and both have blown or have a leaking pinion seal. Maybe just me but keep your eyes on it

What is causing this do you know? Too powerful of a motor? Or is the 10 bolt just that prone to failure?

 

[78C10BigTen]

What is causing this do you know? Too powerful of a motor? Or is the 10 bolt just that prone to failure?

I can tell you its not too much power!!! I honestly dont know

 

[TubeTruck]

I know there is a huge difference in passenger car 10 bolt vs 12 bolt but not sure about the trucks. I would assume the same. If you are worried about it grab a 12 bolt out of a '73-'77('78?) truck. You can still get 3.08 or 3.42 gear ratio and keep 6 lugs and they bolt right in. The front is plenty strong enough for no hardcore wheeling or 4wd pulling.

 

[RoryH19]

I know there is a huge difference in passenger car 10 bolt vs 12 bolt but not sure about the trucks. I would assume the same. If you are worried about it grab a 12 bolt out of a '73-'77('78?) truck. You can still get 3.08 or 3.42 gear ratio and keep 6 lugs and they bolt right in. The front is plenty strong enough for no hardcore wheeling or 4wd pulling.

​

12 bolt will be a little better than 10, you can keep the 6 lug and have the highway gear ratio you want.
Will also be able to keep 15" wheels. No need to move spring perches or shock brackets either.

 

[RoryH19]

If you don't want to do an overdrive trans swap, I'd stick with the current 3.08 axles. That 6.2 won't like 4.10's for sure.

Installing a full-carrier type locker or limited slip in the 10 bolt will eliminate one weak area.

You can always install a 6-lug 14sf rear from an '88-'98 truck too if you are worried about strength. But if you really aren't going to tow, haul, of run larger tires, you 'should' be ok.

I have this rear end from the GMT400, much stronger, 9.5 ring and can keep your 15" wheels.
Added bonus is they are almost exactly the same width as the front axle. Not narrower like original.
However you have to move spring perches and shock tabs. They are also harder to find, at least in my area.​

 

[bucket]

I have this rear end from the GMT400, much stronger, 9.5 ring and can keep your 15" wheels.
Added bonus is they are almost exactly the same width as the front axle. Not narrower like original.
However you have to move spring perches and shock tabs. They are also harder to find, at least in my area.​

I've got one too, for my K5. I got it years ago and at the time, it was easy to find. I haven't looked for one since then though.

Worth noting, there was a 2wd and a 4x4 version of this axle. The 4x4 version is the one you want. It's the wide one.

 

[hunters628]

What year range and model am I looking at? 1500 or 2500? I will look into them
Thanks
Hunter

 

[Craig 85]

I did that swap (1/2 ton 3.08 to 3/4 ton 4.10) with my '79 pictured below, but 350/350/203 combo. I was turning almost 3000 RPM at 65-70 MPH with 33" tires after the swap.

You must be registered for see images attach

 

[Bennyt]

What is causing this do you know? Too powerful of a motor? Or is the 10 bolt just that prone to failure?

I believe that the correct seal for a truck 10 or 12 bolt is no longer manufactured and what is being sold is the car seal as its replacement. I may be wrong and have it backwards but worth looking into.

https://www.hagerty.com/articles-videos/articles/2019/06/03/cure-leaky-gm-12-bolt-rear-end

 

[RoryH19]

I've got one too, for my K5. I got it years ago and at the time, it was easy to find. I haven't looked for one since then though.

Worth noting, there was a 2wd and a 4x4 version of this axle. The 4x4 version is the one you want. It's the wide one.

Good point. I believe the 2wd version is even narrower than original.

 

[RoryH19]

What year range and model am I looking at? 1500 or 2500? I will look into them
Thanks
Hunter

Are you asking for the 6 lug 14bsf?
If so, they are in the 88 to 98 GMT400s
Need to find a heavy 1/2 or light duty 3/4 4x4. I think they were in some vans too but don't recall which ones.