Author Topic: 38's on 1/2 ton?  (Read 24291 times)

Offline discot315

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38's on 1/2 ton?
« on: April 12, 2011, 04:50:18 PM »
Hey I have my 1980 Chevy K10 I just put a new motor in and stuff just got it running good and am driving it every day now.
I did lift it but I am just wondering if I put 38/12.5/15 swampers on my truck (mainly for show) to drive around are they going to be too big? is anything going to break or something? i have 12bolt rear and not sure about the front. it is a heavy half

Thanks guys
1980 K10- 9" lift with 38's. 350 4speed lwb
1976 / 85 front clip K20 - 4" lift with 33's. 350 4speed lwb

Offline bake74

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Re: 38's on 1/2 ton?
« Reply #1 on: April 12, 2011, 04:56:11 PM »
     I believe Irish is running 38's with a 6" lift and some trimming of fenders, and there are a couple of others running 38's.  How much lift did you install ?  A standard 6" states 37" tall tires, but if you are not going serious off roading or jumping your truck, then you should be able to have 38's with a 6" lift.
     Your 12 bolt will be fine unless you have 500 hp under your hood.  You should have a Dana 44 up front, I believe 73 - 80 they ran Dana 44's on 1/2 tons.
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Offline beastie_3

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Re: 38's on 1/2 ton?
« Reply #2 on: April 12, 2011, 05:38:59 PM »
I would upgrade axles if your running over 35 in tires.

Offline slammed79

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Re: 38's on 1/2 ton?
« Reply #3 on: April 12, 2011, 05:52:56 PM »
I would upgrade axles if your running over 35 in tires.

X2
74 C10 Long bed 350/SM465 Lowered on 20's

Praise the lowered

Offline 4x4orbust

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Re: 38's on 1/2 ton?
« Reply #4 on: April 12, 2011, 06:43:38 PM »
if you are easy on the go-juice the 10 bolts will survive.....but don't be surprised when they go boom
1982 chevy K-10 SWB, 355 th350/np208. 2.5"lift, 33" swampers, headers/duals,  current project

Offline Irish_Alley

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Re: 38's on 1/2 ton?
« Reply #5 on: April 12, 2011, 06:57:57 PM »
You can run 38s on 1/2 ton. Like stated the Dana 44 is half ton and 3/4 the only difference is pretty much lug pattern.  I run that on mine with a full floater 14 bolt I run it I'm the mud and break something about every year but that's in the mud. If you on the street you will be ok even if you hit some mud every now and then. I've had my 38s in the mud up to the rockers. And didn't break nothing. But I was in a little ditch and snapped my axle shaft on the front.
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Offline choptop

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Re: 38's on 1/2 ton?
« Reply #6 on: April 12, 2011, 08:36:26 PM »
Theyll work for what your wanting to do except the fact that anytime you turn into a drive that causes any articulation, it will rub. 37s as stated I believe is pushing the limit. It looks good, but the noice when it rubs is gut wrenching.
76 C10 Choptop,76 C10 Swb
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Offline discot315

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Re: 38's on 1/2 ton?
« Reply #7 on: April 13, 2011, 12:09:07 AM »
Alright thats awesome, Im not guna be doing too much but driving to work/school really lol for now and yeah I figured it would break something eventually like in the rear but for now Im going to see how it is. I lifted it 3" body lift when I did the motor but its going back in the shop soon I have to figure out where the rear of the trannys leaking so im puting a 6" suspension lift while its in there. Thanks for the replys and Choptop what are those tires in the pic and how bigs the lift?? I feel better knowing others are doing what I want to do lol  ;D
1980 K10- 9" lift with 38's. 350 4speed lwb
1976 / 85 front clip K20 - 4" lift with 33's. 350 4speed lwb

Offline Irish_Alley

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Re: 38's on 1/2 ton?
« Reply #8 on: April 13, 2011, 09:16:42 AM »
With the body lift you will be good. Side note my buddy is running 44s on a 10 bolt with better luck than I have
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline DustyRusty

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Re: 38's on 1/2 ton?
« Reply #9 on: April 13, 2011, 02:52:47 PM »
Couple things haven't been discussed:  1) The effectiveness of your brakes with the proposed setup.  If you are going 'mostly for show' and are a prudent driver, you will probably be okay.  If you like to make fast stops your brakes are marginal with the current setup;  2) Your gas mileage will also suffer because you will likely have to be tooling around in 1st and 2nd gear most of the time with that granny four-speed.  3) The clutch may suffer because you will likely have to slip it to get everything going - you will just need to be aware of this. 

Good luck with your truck.

Rusty
1975 K-10 SWB Fleetside - 350/SM465/NP205/D44F 12-boltR, 3.73 gears.  Original owner.
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Offline choptop

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Re: 38's on 1/2 ton?
« Reply #10 on: April 14, 2011, 06:57:12 AM »
If memory suits me right, the tires are 38x12.50/15 Super Swampers. I know the size is right, not sure on the tire make. That pic was taken with just a 6 inch lift. If you have the 3 inch body lift already, adding the 6 inch lift is perfect. You wont have many clearance issues, if any at all. If this is the way you plan on keeping it for a long time, I real recommend upgrading gears to at least 4:56s
76 C10 Choptop,76 C10 Swb
85 C10, 85 K10, 85 K20,86 C10,86 K10 (all extended cabs)
86 C30 extended crewcab

Offline ehjorten

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Re: 38's on 1/2 ton?
« Reply #11 on: May 10, 2011, 09:35:56 AM »
You'll want to replace the cups and springs over the knuckles in the front end.  37+" tires are too big for the stock springs and you will get the dreaded death wobble.  Some people just shim the stock springs but you have to be careful that you don't put them in coil bind.  ORD makes a great kit with heavier springs and new ball cups.
-Erik-
1991 V3500 - Gen V TBI 454, 4L80E, NP205, 14 bolt FF, D60, 8" Lift on 35s
1977 K20 Silverado - 350, THM350, NP203, 14 bolt FF, D44, Stock Lift on 31s
1969 Chevelle Malibu Sport Coupe - EFI350, THM350
1968 Chevrolet Step-side Pickup - 300HP L6

Offline discot315

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Re: 38's on 1/2 ton?
« Reply #12 on: June 27, 2011, 12:51:15 AM »
Ya those are the same tires I have, they do look like Swampers they look identical to mine. Im thinking of upgrading the gears just trying to find somewhere with decent prices, and yeah im doing everything in the front end too, Thanks everyone. Trucks in the shop, got the rear mostly lifted it looks funny just the back end way up lol
1980 K10- 9" lift with 38's. 350 4speed lwb
1976 / 85 front clip K20 - 4" lift with 33's. 350 4speed lwb

Offline discot315

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Re: 38's on 1/2 ton?
« Reply #13 on: August 03, 2011, 01:36:00 AM »
Also I was wondering what would happen if I run the 38's with the stock 373 gears? is it just going to affect my gas milage? Im planning on upgrading the gears eventually and currently the trucks still on 33's but im just wondering. Thanks guys
1980 K10- 9" lift with 38's. 350 4speed lwb
1976 / 85 front clip K20 - 4" lift with 33's. 350 4speed lwb

Offline ehjorten

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Re: 38's on 1/2 ton?
« Reply #14 on: August 03, 2011, 08:39:09 AM »
It is going to be a dog on 38s with the 3.73:1s.  With the 38s and the 3.73s it is going to run like it has something slightly lower than 3.31s in it now.  To get the performance back with 38s you are going to need something around 4.30, so the best bet is 4.56s.  This will actually be a little lower geared than it acts now, but not by much.
-Erik-
1991 V3500 - Gen V TBI 454, 4L80E, NP205, 14 bolt FF, D60, 8" Lift on 35s
1977 K20 Silverado - 350, THM350, NP203, 14 bolt FF, D44, Stock Lift on 31s
1969 Chevelle Malibu Sport Coupe - EFI350, THM350
1968 Chevrolet Step-side Pickup - 300HP L6