RE: Contemplating 4x4 Conversion

OK, folks as my health has improved over the last year and a half I find myself ready to start working on one of the vans.

After watching Vanish & Donivan working on Vanish's Econo-No-Door I find myself considering doing the same to my 66 Panel.

Question is: What axles work the best under a 1st gen Chevy? Now obviously the spring perches will need to be moved to fit and adjusted for pinion angle as well.

Starting from scratch on this so and help, advice, ideas or tips would be greatly appreciated.

** The van is currently a rolling shell with a V8 doghouse already installed.

Thanks in advanced!
~DanTheVanMan

Doc Yukon has 70's era full size Blazer axles under his 4x4 conversion, they have been working well for a few decades now. Not sure if the spring perches line up, but the axle width looks stock and 31" tires fit nicely.

Good to know! Thank you...

Anyone else?

For what it's worth, I think the earlies look cool as heck with the 4wd conversion. I've heard most guys use the old K5 Blazer running gear too. I had a '76 Blazer and one thing I never liked about the axles on it was that the rear end is narrower than the front end.
I guess what running gear you choose should depend on how high you want to lift it and how big of tires you want to run. I guess your intended driving habits ought to be taken into consideration too. And of course, $$$.
You might want to look in to Jeep CJ, pre '85 Toyota pickup or maybe S10 gear. If you're doing the swap on a 90", there's not a lot of room for the transfer case and driveshafts. I like Donivans one friend that lifted his van but kept it 2wd. I can't remember his name but it's a blue and white van.
I'm jealous!!

I'll be interested to follow your progress, being in the middle of a 4x4 conversion on a 108 second generation. I've moved the engine back 16 inches to run a bench front seat, which essentially puts me in the realm of a 90, and with a 700r transmission and the 13 inch long NP241 transfer case, the rear drive shaft is down to that of a Jeep Wrangler at 16.5 inches.  This is a "passenger side drop" transfer case. It and the axles are out of a 1990 K5 Blazer, the rear fitting perfectly at a flange to flange width of 64 inches. The front was 3.25" wider, and I narrowed the right side by that amount and had a shorter right axle machined. With some judicious cutting and grinding you can get the differential pumpkin right up against the passenger side spring to help with drive shaft clearance beside the transmission and underneath the starter...every inch will trouble you. There's a bunch of small modern starters that can help with this, but in general, the higher you raise the vehicle and/or engine, the greater the angle between the driveline axis and front driveshaft axis, thereby helping with clearance issues. New spring perches and welding will be necessary to get pinion and caster angles working in your favor, and in my case the front shaft will be pretty long due to moving the engine back. I might have to run a two piece, which in some ways, can literally skirt around the above problems. A few remaining problems: the narrowed front axle even with non-monsterous 225-70r-15 tires causes the driver side front tire to rub against the drag link a good inch before full right rack... running the stock width would likely avoid this. I'm also concerned about the  8 degree caster specs for the Blazers and pickup trucks of that era...probably because the king pin angle points to a spot inside of the tire tread with a lot of scrub radius that needs to be countered...they also run 1.5 degree positive camber to diminish some of the scrub. All those trucks had power steering, so I'm wondering how hard steering will be to run without... might need a 20" steering wheel out of a big rig. For anyone with 4x4 experience, can you help us out?....should have mentioned that I'm running the front axle above the springs, having stiffened and arched them a bit more with add-a-springs. In all of this you need to keep the draglink at roughly the same downward slope to the steering arm, or you will get into problems with bump steer. Lastly, I might have to put a notch in the frame where the drag link ball joint attaches to the steering arm, as it's close, and you don't want any interference with suspension travel...if you are going for a high roller, and/or stick with the wider axle dimensions, this won't be a problem. Hope this helps.

To Dan and Mr. Olins, I'm really interested in following a 4wd build. The more I think about it, lifting a van should be a lot easier than lowering one. I think there are some possible advantages too. V, you said you moved your motor back 16" so you could run a bench seat. My thought was to look at blocking down the motor and trans to accomplish this instead. The front, top of the doghouse is only about 6" higher than the wheel well so if you could drop your engine and d.h. lid down enough to make a bench seat work you would be working with a transfer case that sits closer to center of the wheelbase if not forward of center. Another advantage of this would be that you would also bring the radiator down more into the wind.
All of the steering and clearance issues you talked about are obviously things I can't address without being there with you but I'm sure you will find a way to make it all work. I installed an electric power steering unit in my van and it works like a charm. I would be concerned about using one like mine to turn some big ol' mudders though. The power turns the steering shaft, thereby putting more pressure on the steering box. Look at epas online https://epasperformance.com/products/electric-rack-pinion He's making an electric rack style unit that may be worth looking into.

Well folks,
I am just at the "Gathering of Information" at this stage. I have a set of 87 K5 axles I plan on using. However I have since made the decision to move back to Michigan from here in NE Florida this summer so the 4x4 project will have to be put on hold for now. However I will continue to collect any and all info to help make the project go as smooth as possible! :/ So any info, similar project links would be greatly appreciated...  

~Dan

....talking about power steering units...Summit lists universal Borgeson hydraulic units, 999001, 999003, and 999015 that look like they would easily adapt to our vans.

V. Olins wrote:....talking about power steering units...Summit lists universal Borgeson hydraulic units, 999001, 999003, and 999015 that look like they would easily adapt to our vans.

"AWESOME!!!"