pro/con of 3/4 or 1 ton axle swap

[ramack]

Hey,

Just looking ahead about doing a axle swap on my '79K5. For you guys that have done it, which it the better way to go...3/4 or 1 ton?

This is going to be kind of an all-around K5. Trail use, camping, towing etc. I'll eventually put 35's on it and a suspension lift. I have a 4 spd and would like to put a doubler on it too.

Rich

 

[77_Jimmy]

If you or someone you know can weld go 1 ton. If not go 1 ton in front and 3/4 in rear. I did the latter and it was 100% bolt in. For me the cost of buying the axles and rebuilding them hub to hub was right at 3500 bucks. Then the wheels and tires and lift were more.

 

[munepit]

No real downside. You will need 8 lug wheels. Might as well go one ton. If your going 3/4, might as well add another 1/4! I wish I would have done it a long time ago. When I put in my 14 bolt, I didn't have to weld anything. It dropped right in. That was 14 yrs ago. Hell, I am switching my rear U Joint right now, doing the combo joint. Go with the one ton if you can afford it.

 

[munepit]

If you or someone you know can weld go 1 ton. If not go 1 ton in front and 3/4 in rear. I did the latter and it was 100% bolt in. For me the cost of buying the axles and rebuilding them hub to hub was right at 3500 bucks. Then the wheels and tires and lift were more.

That's a lot. Must be some sweet axles. I have $1500 in mine. I regeared to 5.13 and have a brand new Detroit in the rear.

 

[obijuan]

why 1 tons when you only have 35s? dana 60s are overrated, a set of 3/4 tons will be more than enough for you. and they bolt in.

 

[munepit]

Doesn't the 60 just bolt in also. 60s are overrated? Never heard that before. I have bent many of dana 44 axle tubes. I hope I don't bend a 60 long tube.

 

[obijuan]

Doesn't the 60 just bolt in also. 60s are overrated? Never heard that before. I have bent many of dana 44 axle tubes. I hope I don't bend a 60 long tube.

yes 60s are very over rated. dont fall in and get brainwashed that the ten bolt/dana 44 is a toothpick.

"eventually put 35s" he says. why in the hell would he drop 1000 bucks when he could be wheelin and get some seat time instead of wrenching on a truck with grass growing around it.

all too often i see guys go one ton and the truck sits for 2 years, i dont knwo about yall but 1000 bucks is a METRIC SHIIT TON of money for me.

a dana 44 shafts set is $24 a side at the local yard. lets go wheel!

 

[munepit]

You are right. No need for one tons on 35's. I was just curious, that's why I asked. My rig sat for 13yrs. That will never happen again! I just did a pretty hard trail with 3/4 ton axles and 38s. Worked just fine! If I. Had a locker it would have been a lot easier too!

 

[ramack]

How I plan to proceed is run 33x10.50 for now. While the rubber is wearing off of these, start collectin' stuff. Start with 3/4-1 ton axles and rebuilt them and re-gear to 4.88 or 5.13. I'll probably lock the rear, possibly the front too. And have them both switchable. Find parts for a doubler. When I get this far put on a 4-6 inch suspension lift. Then if I have any money left, ha, buy 35 (or so) inch tires.

Thanks for the input, I'm open to all ideas...

Rich

 

[K85 Octane]

I don't know much, so my input is limited

but the strength difference between a 1ton and 3/4ton 14bff is zero (I always thought) with the 1ton I think you get bigger brakes, but it's not needed. A 3/4 you bolt right up, but the 1ton you need to move spring perches. I have a "3/4"ton 14bff.

The only 1ton you would really want is the D60. If you wheel really hard or plan on running a locker in the front, then the D60 might be the ticket to end any trail worries. If you are talking doubler and lockers, this doesn't sound like a fireroad mall crawler to me.
(JMO on iffy facts)

 

[cabledawg]

For mild-moderate trail driving, you could get away with keeping the 10bolts on there. Even with a locker, I've heard of a few folks running 35's locked on a 10b, but they arent using high horsepower or lots of wheel speed. That's what'll kill a 10b quick. You get a tire spinning then it grabs and *SNAP* goes the shaft.

 

[ramack]

, this doesn't sound like a fireroad mall crawler to me.

This thing will probably never see a mall, unless there's a parts store there, ha.

The reason I want a doubler is that even with the 33's I can't slow down enough going over rocks. I see I have two options for gearing down. Either re-gear the diff's or put in a doubler. If I re-gear the diff's, that's going to kill me on the highway. Going with the doubler, I can gear way down as needed.

Rich

 

[throttleissues]

For mild-moderate trail driving, you could get away with keeping the 10bolts on there. Even with a locker, I've heard of a few folks running 35's locked on a 10b, but they arent using high horsepower or lots of wheel speed. That's what'll kill a 10b quick. You get a tire spinning then it grabs and *SNAP* goes the shaft.

Chickenrammit on this site has been quite successful with 10bolts, 35s and lockers with alloys shafts in the rear ($110 ea) and carries spares for the front. I've been amazed at how far a little common sense takes him in the rocks.
Ramack, if you're only lookinf at 35s, why not consider tha 14sf rear axle and 3/4ton front? I still recommend the 8lug models due to the brake upgrade over 1/2tons. Otherwise, you'll be hanging up more with a 14ff on 35s than you are with your 10b and 33s.

 

[POORBOYK5]

The reason I want a doubler is that even with the 33's I can't slow down enough going over rocks. I see I have two options for gearing down. Either re-gear the diff's or put in a doubler. If I re-gear the diff's, that's going to kill me on the highway. Going with the doubler, I can gear way down as needed.

Rich

what gears and t-case do you have? A Np241 has a 2.72:1 ratio in low, which is very good for a stock inexpensive t case. A doubler can run you a metric **** ton of money too! And If you're not going hardcore, a Np241 will hold up just fine. Im running one with 42's and 5.13's. why spend the money on a doubler and gain all that weight and have to mess with new drivelines. shafts can be had at a u pull yard cheap. Just my .02

 

[ramack]

Ramack, if you're only lookinf at 35s, why not consider tha 14sf rear axle and 3/4ton front? I still recommend the 8lug models due to the brake upgrade over 1/2tons. Otherwise, you'll be hanging up more with a 14ff on 35s than you are with your 10b and 33s.

Ground clearance....this is one thing I'm weighing...I'm surprised, the past couple trail runs I've gone on, I haven't gotten hung up. But I did use the transfer case plate going up Radical Hill, ha.

Is the ground clearance on the 14BFF that much less than the 12B?

I have a friend who is going to sell me within the next year or so, his '78 3/4 Chevy P/U. I'm mainly interested in the axles, maybe the transfer case if it's in better condition than what I already have. So I'm debating swapping those axles or going up to 1 ton.

 

[1BEATK5]

14 bolts hang way down,and have a lip that gets stuck on everything. yes you can grind most of the lip off, but they still hang down alot. they also weigh 525lbs. high 400s with discs instead of drums.
i think a 3/4 front and a sf14 would get you what you need, atlest untill you decide that you want to run 38s

 

[ramack]

what gears and t-case do you have?

I am assuming 3.73s (same as my '77). I've only had it a couple months and I haven't taken the time to clock the gear ratio. The transfer case is a NP205.

As far as the new driveshafts if going with a doubler...I haven't made any measurements, but I had thought about pushing the motor/transmission forward instead of pushing the transfer case back.

what gears and t-case do you have? A Np241 has a 2.72:1 ratio in low, which is very good for a stock inexpensive t case. A doubler can run you a metric **** ton of money too! And If you're not going hardcore, a Np241 will hold up just fine. Im running one with 42's and 5.13's. why spend the money on a doubler and gain all that weight and have to mess with new drivelines. shafts can be had at a u pull yard cheap. Just my .02

 

[79rustyk10]

I went to 3/4ton axles just for the better gearing. I plan to stay in the 35" range too, so the D44 front should be fine for me in the forseeable future.

Ive seen people beat 10 bolt fronts like crazy with 38's and have to replace a U-joint or two is all. I think that was an open carrier too though.

dont fall into the whole needing a D60 front for anything bigger than 31's thing like so many guys do. run with what you have and if you keep tearing **** up, then go to the 60.

 

[cabledawg]

Here's my take on the doubler: good luck. I had a hell of a time finding a range box and adapter that anyone was willing to let go of, and even then the adapter was a fluke that someone had one in good shape. Your best bet for the doubler is to find a vehicle with the 465/203 combo in it already, then take what you need and sell the rest. There are other ways of doing a doubler behind a 465, but the stock adapter and 203 is the best, but also the hardest to source parts for.

The good thing is however, the doubler adds only an inch or so onto the overall length when used behind a 465 with the stock 203 adapter vs the 465/205 combo. SO you could very easily scoot the engine forward a bit so you dont have to change driveshafts

 

[6.2Blazer]

I ran a 10-bolt front and 14FF rear with 35's for a couple years on the trail. Previously I had a 10-bolt rear with the same tires. Honestly I really didn't notice any difference in regards to off-road performance and ground clearance when going between the rear 10-bolt and 14FF.....I do have to say that I had the lip ground down flush on the 14FF. The one thing I did gain was a lot of confidence knowing that the rear axle was basically bulletproof.

I don't know how you drive, but would probably say a D60 front and doubler is pretty overkill for a rig on 33's and possibly 35's in the future.

For gears, you said you had an 205 and if an automatic (TH350 or 400) then the crawl ratio is pretty crappy.