New k5..check it out..need help

[reece13]

Hello everyone,

Im new to this site. Im not new the 4wd world but am kinda new to the GM 4wd part.

Recently i've acquired an 89 k5. It has a 350/700r4/np241. It runs and drives great. It has been well taken care of all its life...so..heres the issue..It has the factory 10 bolts and its lifted about 8" or so with 37 13.50 15s

I def. dont want to burn up the 700r4 so a re-gear to 4.56 or 4.88 is in the future, BUT im not sure if i should put that money in 10bolt. Just some fyi this truck is about 50% city driving, 30% hwy (65-75mph) and the other is for camping and mabye loggin roads or occasional open field mud. I dont run it hard is what im getting at.

So....should i try to get maybe a 14sf so i can keep my wheels/tires and keep the front 10bolt and beef it up..or what is the best option here that wont break me too much???? thanx for any advice

 

[blazinzuk]

Thats a good pick get a 14 b sf 6 lug. Its a strong axle and will handle those tires with ease.

Although if you pay for the gear setup to 4.56 on a 10 bolt and a sf 14b, you may find yourself close to or even over the cost of a set of one tons, which if you look hard enough you can find with 4.56s.

Cost of gears and install kits is going to be anywhere from 500-800 round about, installation at the low end is going to around 200 an end and the high end is upwards of 500 an end. So looking at near a grand for a gear change ( after buying the SF 14b) if not well over a grand.

Shouldn't be to terribly hard to find a set of tons from a truck ( mostly are cucvs) with 4.56s ( if you get it from a cucv it will have a rear locker).

Thats what I would do. If you are doing the gears yourself then certainly its way cheaper

 

[reece13]

now that u say it, that does sound like a better idea than keeping the 10 bolt front. im pretty sure i could find a set of 1 tons in my area without too much hard looking.

would i be able to keep the 241? and how hard is it to set up the rear axle when swapping to 1 tons? i know the 14 sf is a direct swap. dont get me wrong the 1 ton swap sounds awesome, but it seems like a lot of other work involved that has hidden costs. My truck already has custom driveshafts on it so im not sure if i could use them, and then i would have to change wheels and tires.....the fab work isnt too much of a big deal, its just im not sure what i would run in to.

do u have the 1 tons or know someone who has done it?

 

[K5dreamer]

The D60 is a direct bolt in on the front from what I've heard (and personally hoping when I get around it)

For the rear axle, 3/4 ton axles are a direct bolt in, but for a 1 ton axle the spring perches and shock mounts (?) need to be adjusted.

 

[blazinzuk]

now that u say it, that does sound like a better idea than keeping the 10 bolt front. im pretty sure i could find a set of 1 tons in my area without too much hard looking.

would i be able to keep the 241? and how hard is it to set up the rear axle when swapping to 1 tons? i know the 14 sf is a direct swap. dont get me wrong the 1 ton swap sounds awesome, but it seems like a lot of other work involved that has hidden costs. My truck already has custom driveshafts on it so im not sure if i could use them, and then i would have to change wheels and tires.....the fab work isnt too much of a big deal, its just im not sure what i would run in to.

do u have the 1 tons or know someone who has done it?

You can search and find most of those answers.

But the front is a straight swap literally IF you have the u bolts and u bolt plates from the 60 obviously the 10b ones won't work. I simply drilled out my brake lines to accommodate the larger 60 banjo bolt for the brakes.

The 14 SF 6 lug ( which I think is what you are talking about) is not a direct swap because it comes from a newer truck, perches shock mounts brakes it all needs changed.

A 3/4 ton 14 bolt ( which with 4.56s is rare) is a direct bolt in once again assuming u bolts and plates. You will need an adapter u joint to use your current driveshaft.

A one ton 14 bolt ( if you find cucv axles this is what it will be) the perches will need to be moved, not sure about shock mounts I think they are the same. Brakes are easy to adapt as are e brake cables.

So there you have it. I was thinking about this thread earlier remember the one tons you want will more than likely be found under a CUCV military truck, they usually get advertised as such so should be easy to find. In addition to the 4.56 you will get a rear detroit if you find CUCV axles.

Now the caveat to that if I was running a 37 and a 700 I would probably choose to gear deeper. But the tons would get you a decent ratio and a huge strength advantage

 

[Deuling]

Dont put a 14bsf in the rear if you get a 60 up front. That would be silly Imo. A cucv combo will have the same gearing and the axles will bolt right in with the exception of moving perches on the rear axle. (which isnt hard with a grinder and welder).

 

[chulisohombre]

If all you doing is road driving and light offroad and camping, the front ten bolt should do alright. You Could get a match set for a good price and hopefully geared better than what you have if you look around and junkyards may be avle to find you what you want. One tons would be better and all that but ou will need to do the mods to the rear axle and driveshaft. Also would need new rims and tires. With the 700r trans you can run it in 3rd gear and not use od to help it last longer. When I'm towing I don't use of at all with no bad effect on the tranny.

 

[ktmoutfront]

I have the same setup you have now. Except for a Currie extreme duty 9+ rear. I am not going to comment on strength, only gearing.

With the 37's, go 4.88:1. I have 35's and the trans hunts for OD at 65mph. And I am running 4.56:1. Wish I had done 4.88:1 originally.

 

[reece13]

thanx for all the input everyone...

I have one more question....if i just re-geared for now (not saying thats what i want to do), what about this stupid gov-lock i have in the rear? obviously i shouldnt re-use this thing, especially with a 4.56 gear or lower right??....

 

[chulisohombre]

The gov loc is natirious for blowing up with larger than stock tires. I don't know what the gear break is for ten bolts are, but I think it is 4.56 someone said before. Someone else chime in on that I'm sure. For site you would need a good carrier and spider gears or put in a locker. It still pushin the axle hard with those size tires on ten bolts. You could build it for a few hundred bucks to be tougher, but then you still have ten bolts with the smallish ring and pinion. You would keep ground clearance but lose the strength you could get by going to a stronger axle to begin with. The 14 sf is a perfect swap if you don't want to go crazy and you get to keep your current wheels and tires.

 

[K85 Octane]

drive it for now, keep an eye out for a deal on used gears or a matching 10b/14sf from someone elses project. If you go 1tons, you need new rims. Not sure how nice your current ones are. I wouldn't put a D60 up front unless you need the strength. It's about 150lbs heavier than a 10b and you can feel it, I can coming from a D44.

If the truck is sound now, run it for the next year or so while looking out for deals. I sound like a broken record when I say get to know the truck before spending $$$ on unnecessary parts.

 

[82355]

I hate half ton axles. They break way too easy. My vote is look for a set of 3/4 ton axles, or a set of one ton axles if you happen to come across a set. If you just keep driving it as it is while you look for axles, you can usually come across a good deal.

Martin

 

[chulisohombre]

If you are easy on it the ten bolts can last just have to watch the balljoints bearings and axle u joints. I've had my truck 12 years and only broke 2 I joints and have done the bearings and ball joints a couple of times. I run mostly easy trails and not too hard on it on the rocks. My rear end was my problem with breaking so I went 3/4 ton and haven't had a problem since.