C20 14 Bolt Conversion

[Supergas]

For the folks who have converted the Eaton axle to a newer 14 Bolt, I have a question..

Did you narrow the 14 Bolt to the Eaton width or just use a different back spacing rear wheels??

I am probably going to do this conversion and think that it should be narrowed, but would appreciate some feedback on how you did yours..

Thanks,

Supergas

[franken]

Why the change? Can't get drums? Different ratio? You can do a conversion to disk pretty easily, but unless you get the Eldorado calipers, the E-brake is an issue.
As I recall 66 spring perches are the same width as 67-72. Early square 14 bolts on a cab and chassis had the same spring perch width as 67-72. Also there are two spindle sizes for the 14 bolt. one for SRW and one for DRW, so you have some flexibility there. Last, the shocks are staggered on the squares so a bit of fab will be needed there...
The late model metric 14 bolts are wider as I recall. Then of course there are the simifloat versions. I guessed you meant the fill float 14B.

I suggest a read of the 14 bolt bible thread on pirate4x4.

[urmyboyblue]

I just replace my Eaton with a 14 bolt. I was not concerned with keeping the track the same, so I cannot answer your question exactly. I used some wheels off of Ebay- not sure of the back spacing difference. This is a ground up restomod. However, the 14 bolt bolts right in, but you will have to modify your driveshaft to the right length and u joint. The rear disk brakes use mid 70's K30 or K20 front calipers and rotors. Not sure about the El Dorado stuff the previous guy mentioned. But I am not going to have rear emergency brake- that is a problem. Dual rear wheels hubs are 2" per side narrower than single rear wheel hubs. Narrowing it will give you the opportunity to make it exactly like you want it, but it will be expensive.

[franken]

The eldo calipers have a mechanical E-brake that the front square body calipers obviously don't. As I mentioned spring perch width is different on most 14 bolts so unless the right one is found, it certainly is not a bolt in.

[ElKotze]

I had to move spring perches and shock mounts, no big deal. U-joints are the same on 3/4-tons.
It moves the rear wheels out a couple of inches, but i like that because the wheels now sit flush with the fenders.

[andyh1956]

What about Van rear axles? I gotta 1 ton '78 Chevy van but I think it has a 60 in it.

[Captainfab]

All full size van differentials are a LOT wider than a truck differential. Like 3-4"

Originally Posted by andyh1956

What about Van rear axles? I gotta 1 ton '78 Chevy van but I think it has a 60 in it.

[mcmlxix]

I swapped a 2005 GMC AAM 14BFF rear with twin piston calipers and DRUM IN HAT emergency brake into my 1972 K5 Blazer. It may have been slightly wider but not that noticeable. Its almost the same track width as the front now. The OEM e-brake setup with over the counter spare parts availability was totally worth it to me. I had to move the spring perches and will need new intermediate e-brake cables.

There are two versions for the trucks too, one is heavy duty behind 3500 and diesel trucks which is easily identified with a balancer at the yoke. I got mine from www.car-parts.com which searches salvage yards. $450 shipped to my local FedEx and that was 410 with G80 posi. Just make sure its complete with calipers and rotors.

[Supergas]

Thanks everyone, I appreciate the feedback.. I was really just trying to get away from having to have the axle narrowed... I now know that most if not all just use the 14BFF as is..so \I will just use the 14BFF with my new steel wheels and if it fits closer to the fender all the better.. will be running 235 or 245 tires so should not have to worry about width too much..

Complete plan is to change both rear and front to late model 3500 SRW this will give me more modern drive-ability while keeping the 66 Truck look.. It will be Disc Front & Drum Rear.. With over the counter parts availability. And of course PB & PS.

I am keeping the original 327 & 4 Speed with new 3.73:1 G80 rear end.. this should make it very versatile..

Again, thanks,

SG