What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Build up questions.

L

LT.

1/2 ton status
Joined
May 25, 2009
Posts
238
Reaction score
3
Location
Los Alamos, New Mexico
Hey y'all,

I don't post up much because I am really a Dodge man but, I have recently bought a 1975 GMC 3/4 ton with a blown tranny. As of now all I really have figured out is that the truck will sit on some 285-75-17 tires and it is for my daughter.

My questions are:
1. What transmission should I put in place of the original TH-350?
2. I think I want to build a fuel injected 383. What transfer case should I use?
3. The truck needs to be in town friendly and highway friendly. What gears should I look at using?
4. Has anyone else ever seen a long bed, fleet side, with a wooden bed floor? I never had seen one before and it is all original.
5. I am a huge fan of Off Road Design and I am looking for about 4 inches of lift. What pieces should I really consider to accommodate the tires I want to run?
6. Should I be thinking about replacing the front axle with a 60?

I read the board frequently but, don't post up much. I don't generally have much to offer but, I would appreciate any input and insight y'all may have. Thank you in advance.

LT.
 
1. Easiest would be another th350
2. 208 is common, light and good gearing.
3. with the tire size you mentioned (and assuming you would stay with a th350 or similiar) i would be looking at 3.42 or 3.73
4. I have not
5. Front lift springs, and shackle flip in rear. Fairly cheap, and will maintain a decent ride. If you wanted to go cheaper you could use blocks in the rear, but depends on your budget and longterm use.
6. You dont need a d60 with those tires. Unless you plan on seriously beating the crap out of it, which i doubt with the way it seems you are building it.
 
Howdy Rob!!!!

I would try to throw a 700 in it. Got the overdrive which is real nice on the highway.

Thats not a very big tire at all so no need to put a 60 up there at all.

Its probably got 4.10s with the tire size and stuff I would leave them if you put the 700 in. If you leave the 350 I would go down to a 3.73
 
I would definitely stay away from the 60. 3/4 ton running gear is plenty strong for basically street tires and highway use.
The factory built a strong dependable vehicle with good driving manners. The farther you get away from stock, the more work it is to get back those manners.

Your daughter does not need to be dealing with death wobble.

The heavy stuff only needs to be invoked when you are going to be doing hard core wheeling.

Stay close to stock, only do mods that improve safety and/or reliability, and you will give your daughter a vehicle that will get her where she wants to go and back home safely.
I would beef up the front and rear bumpers a lot. Looks are good, but go for function over looks.
You want some serious steel between your daughter and that idiot that runs the stop sign in front of her.
If the truck drives through his car and comes out the other side with only minor scratches and no damage to her, too bad for him.....
 
Thank guys! I really appreciate all the help. I cant remember ever assembling a sold axle vehicle and not building it for hard off road use. I am still struggling with the whole street use 4x4 with solid axles. I am excited to build this truck. One of the two vehicles i learned to drive in was a 1975 GMC 3/4 ton.

Eric- I hoped you would chime in here. I figured you would know how to assemble this kind of truck for a little girl.

LT.
 
Okay so, it sounds like a TH-700 R4 will be going in with the little 383. The X-case will probably stay a NP-203, maybe a 205. Stock axles, on 17X9 Black Rock wheels with a 4 1/2" back space. Rear axle will get limited slip maybe even the front axle. Tires will be Toyo Open Country MT's sized 285-75-17's. Tuff Country 4" lift springs up front, rear 2 1/2" rear shackle flip with 2" Tuff Country rear springs. All grease-able bolts, new polyurethane bushings, and a 4" steering arm. I want to run the Off Road Design FUSH, front and rear bumpers, as well as the rear shackle flip. All parts will be ordered from Off Road Design. I love their products. New bed floor will be ordered from Horkey's and will be Red Oak with stainless steel hardware. New front seat and color matched interior.

I am on the fence about the cross over steering on the Dana 44 axle. Does anyone have any ideas or thoughts about it?

Thanks again in advance for all the help.

LT.
 
I would do crossover cause every truck I have ever done it to, the steering feel has improved, think about eliminating the rag joint on the box too. Cheap way is an XJ steering shaft, expensive way is a borgeson shaft, being a dodge guy I know you have used those before :D:

I would keep a 208 over a 205 or 203 in this truck slip yoke should not be problematic at all with the wheelbase and small lift. Unless you keep the 203 full time then I would leave it
 
blazinzuk said:
I would do crossover cause every truck I have ever done it to, the steering feel has improved, think about eliminating the rag joint on the box too. Cheap way is an XJ steering shaft, expensive way is a borgeson shaft, being a dodge guy I know you have used those before :D:

I would keep a 208 over a 205 or 203 in this truck slip yoke should not be problematic at all with the wheelbase and small lift. Unless you keep the 203 full time then I would leave it
Click to expand...

I just got off the phone with Off Road Design about the transfer case and the transmission. I think I am going to put a NP-205 behind the 700R4. Then we can have a part time case and try to keep double digits for mileage.

Thank you for the input on the steering. I will end up with the cross over after all.

LT.
 
This project maybe taking a different turn now. My brother has put the idea in my head to use a 5.3 liter ls engine and a matching transmission. If I were to go this route is there a way to either keep the 203 case or go with a 205? I have done a few searches but, it seems like most are going with something different. Any ideas on what is the best option here?

Thank you again in advance.

LT.
 
That 5.3L will probably be mated with a 4L60E, if it is, it will be the later 6 bolt tailhousing with removable bellhousing.

Getting a 203 in there isn't too bad, but you'd have to take it apart to drill/tap the face, plus you'd need a mechanical-to-electric speedometer adapter. If you want full time 4x4 it's a good way to go, if you don't care about that, I'd do something else.

The 205 can be done but takes an Advance Adapters 6-to-4 bolt reducer, a new output shaft in the trans and then TH350/NP205 parts. Again, an ok way to go but not cheap, would need to be converted to electric VSS as well.

I would recommend trying to source an NP241 from a 90-91 Blazer or 1/2 ton Suburban with an automatic. It's a good t-case that's plenty strong for what you're doing, it literally bolts right up and it has the electric VSS to keep the engine and trans happy. A little on the rare side but they are out there.

A Chevy NP208 from behind a 700R4 will bolt up as well but would need a converter for an electric VSS.
 
to convert from mechanical to electric speedo isnt bad, i got mine from JJ (Ion) here on the site
 
38377k5 said:
Getting a 203 in there isn't too bad, but you'd have to take it apart to drill/tap the face, plus you'd need a mechanical-to-electric speedometer adapter. If you want full time 4x4 it's a good way to go, if you don't care about that, I'd do something else.

.
Click to expand...

If that would work as good as my old 04 Durango did with full time 4wd I would definitely recommend this for your daughter. That vehicle had awesome control and stability in the snow.
I love your other builds and am looking forward to seeing where this one goes:thumb:
 
Thank you for the props y'all. Okay so, what if i really dont care what transfer case goes in there? I would prefer a part time case for mileage but, the full time case does have some merits to the design. Would it be better to drop another case in? What is the easiest, best way to go? Am i looking at this all wrong?

LT.
 
LT. said:
Thank you for the props y'all. Okay so, what if i really dont care what transfer case goes in there? I would prefer a part time case for mileage but, the full time case does have some merits to the design. Would it be better to drop another case in? What is the easiest, best way to go? Am i looking at this all wrong?

LT.
Click to expand...

The best t-case for you, IMO, is a 90-91 Chevy NP241 behind a 700R4.
 
82355 said:
Just find a 1990 or 1991 Suburban or K5 in the junk yard.

Martin
Click to expand...

I need to get down to albuquerque and check the junk yards out. Getting time away from my family is a bit of a challenge. I have a beautiful little girl and i am wrapped around her little finger very tightly. I will see what i can find.

LT.
 
Next series of questions. I have the wheels picked out as well as the tire size but, I sure could use some ideas as to which lift spring manufacture to go with. Does anyone have a preference for a truck that will see mostly street duty? This is a street truck first and an off road truck second. I will be replacing the front and rear springs no matter what. A nice ride would be preferred. It may get a winch up front at some time but, not right away.

Thanks in advance.

LT.
 
It typically is considered that BDS and Tuff country EZ rides are the softest and smoothest springs.

Pair either one of those with some Bilstiens and it will ride nice
 
You must log in or register to reply here.

Latest Posts

Top Bottom