2WD to 4WD -> What setup?

[Rogier]

I've searched a bit and was looking for some specs that I can give the mechanic that is doing the conversion from 2WD to 4WD for me. I didn't find a good answer so I'm posting here in the suspension area. My question is the following:

What are the detailed undercarriage setup specs that a 4x4 should have if I want to have the same driving experience as I had with the 2wd? Terrain capabilities are not important, the 4x4 is for use in snowy conditions.

Any good post-links or opinions are highly appreciated.

[Dunenutt]

Which truck are you starting with?

[LONGHAIR]

First of all you are never going to have the "same driving experience" with a 4x4, unless you are talking about a very late-model independant suspension.
Either way, if you really need 4 wheel drive in a vehicle that was originally available that way......just buy one. The cost to convert is going to be more than buying an existing 4x4, especially if you are paying someone ele to do the work.

4x4 conversions are much better suited to vehicles that were not offered as 4 wheel drive.

[andrewmp6]

The newer stuff like 88 up i believe the frames are different between the two.The older trucks it can be done but its a lot of work it is cheaper to sell yours and buy a 4x4.

[Rogier]

Thanks for the replies! I know a 4wd will always drive less desirable, but I need it for the snow I'm going to plow through..

Starting truck is a 81 crew. They are extremely rare in Europe, I found just 1 after 2 years of searching. It's approved as being a classic, that means no taxes and very limited insurance cost. Chances of getting an original 4x4 approved in the same way are extremely small, even if I could find one. The amount of support I need is limited, so financially this is the way to go.

I've looked at putting ifs (88 and up) suspension on it, but the frame width is different. Since welding anything significant onto the frame is illegal over here, boxing it to fit ifs is not an option. That leaves me with the option of just swapping the front setup from a 4wd with my 2wd. Donor suburban is available, everything matches 1 on 1, so it will work in the near future.

Back to my original question, can I make improvements to the setup along the way to make it more drive able? Dampers and new leafs is clear, but maybe slightly moving the position of the axles or setting angles on the wheels will improve things?
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[andrewmp6]

The suburban can work you need basicly the whole front suspension the trans the t case and shifter and driveshafts the front should bolt in the rear won't tho.And the trans hump in the floor is different on the 4wds so you'll have to cut and weld it in.Try searching 4x4 swap on here you should find a few done.To get it to ride smoother http://67-72chevytrucks.com/vboard/s...d.php?t=502980

[Rogier]

Looked at some parts and I think I can setup a lot of different variables.

Anyone have a best practice when it comes to road driving a 4x4 for:

Camber
Caster
Toe

Thanks!

[j1970GMC]

Originally Posted by LONGHAIR

First of all you are never going to have the "same driving experience" with a 4x4, unless you are talking about a very late-model independant suspension.
Either way, if you really need 4 wheel drive in a vehicle that was originally available that way......just buy one. The cost to convert is going to be more than buying an existing 4x4, especially if you are paying someone ele to do the work.

4x4 conversions are much better suited to vehicles that were not offered as 4 wheel drive.

I agree with the post above.
I have a 1970 C10 that was converted to a 4x4 with a Dana 44 front end, leaf springs, and an NP205 hooked up to a TH350/327SBC. The ride is MUCH worse than my 2wd 67. I'm not sure, but I would assume a lot of 4x4 conversions would include a straight axle front end, which would ensure the ride is much worse than a 2WD truck. Just my opinion and observation from my trucks.

[Rogier]

Have been discussing to 'weaken' the leaf springs by removing 1 or 2 leafs and adding airbags to compensate. Any thoughts on that?

[andrewmp6]

There is kits to run the 52 rear leafs in the front they are longer and flex more. http://diy4x.com/cart/index.php?rout...product_id=121

[dennislbrooks]

Hi, 3 months ago my 67 short fleet was a 2wd and today is a 4wd. I wanted to use my c10 restored frame and keep it as pleasant a driving machine as I could as a full functioning part trime 4wd. I fabricated when needed and did all labor.

I would do it the same way again.


I used the following on my c10 to get it.

69 4wd suspension mounts however I do believe I could use slghtly modified 73-87. I had a donor 69 k10 rolling chassis.

1972 k10 leaf spring with one of the 3 leaves removed

1975 k10 rear 5 leaf 52 inch springs with overload adding a 2 1/2" lift block -- must be off centered about an inch

1987 np208 behind my 350 turbo

1988 Blazer GM 10 bolt front diff

4wd power steering gear -- i used a 1969 --- others will work

My stock 67 rear diff with perches flipped to top -- i ran rear disc on my c10.

Front rear suspension mounts on the c10 frame must be notched 1 1/8" and add a 1/2" plate spacer for rear rear hanger

Front sway bar 1 1/4" from a 1987 k10.

Let me know if you want a specific picture of something.

[j1970GMC]

Originally Posted by Rogier

Have been discussing to 'weaken' the leaf springs by removing 1 or 2 leafs and adding airbags to compensate. Any thoughts on that?

I'm not sure, but I'd like to know too. I have SkyJacker leaf springs and they are stiff.

[Chevymaniac]

Originally Posted by dennislbrooks

Hi, 3 months ago my 67 short fleet was a 2wd and today is a 4wd. I wanted to use my c10 restored frame and keep it as pleasant a driving machine as I could as a full functioning part trime 4wd. I fabricated when needed and did all labor.

I would do it the same way again.


I used the following on my c10 to get it.

69 4wd suspension mounts however I do believe I could use slghtly modified 73-87. I had a donor 69 k10 rolling chassis.

1972 k10 leaf spring with one of the 3 leaves removed

1975 k10 rear 5 leaf 52 inch springs with overload adding a 2 1/2" lift block -- must be off centered about an inch

1987 np208 behind my 350 turbo

1988 Blazer GM 10 bolt front diff

4wd power steering gear -- i used a 1969 --- others will work

My stock 67 rear diff with perches flipped to top -- i ran rear disc on my c10.

Front rear suspension mounts on the c10 frame must be notched 1 1/8" and add a 1/2" plate spacer for rear rear hanger

Front sway bar 1 1/4" from a 1987 k10.

Let me know if you want a specific picture of something.

Nice job on the 4wd conversion. I'am doing the same thing to my 72 shortbox stepside.

[Chevymaniac]

Question for u Dennislbrooks. What do u mean by notching and plating hangers for rear springs. My truck has the trailing arms, but i'am in the process of buying factory 2wd hangers from a member on this site. I assume by doing this it would be a direct bolt in. Do u have pics of what u are referring to?

[dennislbrooks]

My method

As the 2wd chevy c10/c20 has a rear bowed out frame in the rear for the coils unlike a 4wd frame which is straight, the front rear perch would point toward the tire if mounted flat on the 2wd frame. May be one reason some leave the trailing arm setup. Which may be ok. Probably a softer ride.

The front rear hangers have 6 bolts holding them on instead of the 4 (rivets) oem. The 2 additional bolts are in the botton. You can use one existing hole in frame. The perch is notched 1 1/8" in rear and 1/2" in front.

Rear rear perches are spaced out with a 1/2" solid steel plate.

I used part # 22-553 leaf springs in the rear.

I placed the perches on top of my existing rear axle so I could play with their position before welding.