14-bolt installation question - The 1947 - Present Chevrolet & GMC Truck Message Board Network

4x4 Pray · 12-11-2002, 07:33 PM

I just picked up a free 14-bolt with a locker out of a '78 1 ton chevy. I have a 3/4 ton '70 4x4 with an eaton in it right now. Does anyone know anything about doing this swap? Anyone relocated spring perches before? Sounds like a major pain to me. Also, will the overall width of the axles be the same?

Any advice is welcome. I was excited, but now I'm nervous that I got more work than I bargained for.

Jeff

ozarkhippie · 12-11-2002, 07:40 PM

measure the distance from center to center of the spring perches of each axle. If the 14 bolt came out of a 1 ton it should be the same as the one in your 70, so there should not be any spring perch relocation.

Alexis · 12-11-2002, 07:41 PM

.............hehe your in for some fun. i just finished doin this swap in my 3/4 ton.Things your going to need are the brake brass fitting 3/16 female to 1/4 male(real pain to find so i incountered). Oh and the U-joint strap kit i used was "360-10" napa.

Alexis · 12-11-2002, 07:59 PM

14-bolt FF 4.56 posi

Alexis · 12-11-2002, 08:00 PM

kinda blurry cause i used the program to zoom

4x4 Pray · 12-11-2002, 09:00 PM

thanks for the tips. went and measured my perches and the new perches. mine are about 2.5" narrower. guess the 14 bolt is from a 3/4 ton then.

thanks for the pics too. you looking good. mines covered in rust.

**jerry moss** · 12-11-2002, 09:35 PM

i've done this swap on a few trucks, it takes some time but is well worth the effort. you can buy new spring pads at most speed shops, i use a 4inch grinder to cut off the old pads. grind off and re-use the shock mounts (they're staggered on the 79). you'll need an angle guage to set pinion angle, brake line fittings and longer e-brake cables. i get my e-brake cables redone at nevada speedometer in reno nevada. if you have any questions, feel free to call me, 925-634-2512.

4x4 Pray · 12-11-2002, 10:45 PM

925? WOW, you live right by me! I go to school in San Luis Obispo, but my hometown is in Clayton (right by Concord). That's pretty cool.

Anyway, I appreciate the encouragement. You have inspired me to keep on going on this project. But what's an angle guage look like? And can I set the angle some other way rather than buying the guage? Will it screw things up if just I try to get it as close as I can?

roger0080 · 12-11-2002, 11:20 PM

I've done this to my 71 K20 also.

I'ld rather have the Eaton myself and just pay for the NoSpin diff if you want a locker that bad. You can get a disk brake conversion kit for the Eaton rear end too! Check out: http://members.aol.com/blackbirdstrucks/index4.html

But what I did as others said is you will have to move the spring perches in. I had a shop do mine.
Relocate the shock brackets on the axle, my pinion strap to the yoke and U-joint fit right into the 14-bolt, did a brake job on the 14-bolt since you have it out. The Eaton uses 5/16" brake line to the wheel cylinders where the 14-bolt will use 3/16". No problem. I bought new wheel cylinders for the Eaton and bolted them into the 14-bolt. Ran new 5/16" line from the wheel cylinders to the "T" connection. No fuss no mess.

Hardest part is getting the right pinion angle when it's all done. I had to use some tapered shims and it was pretty close.

-Roger

12-11-2002, 07:33 PM	#1
4x4 Pray Registered User Join Date: Apr 2001 Location: San Luis Obispo, CA Posts: 69	14-bolt installation question I just picked up a free 14-bolt with a locker out of a '78 1 ton chevy. I have a 3/4 ton '70 4x4 with an eaton in it right now. Does anyone know anything about doing this swap? Anyone relocated spring perches before? Sounds like a major pain to me. Also, will the overall width of the axles be the same? Any advice is welcome. I was excited, but now I'm nervous that I got more work than I bargained for. Jeff

12-11-2002, 07:41 PM	#3
Alexis Member since 2000 Join Date: Dec 2000 Location: Mountain View Ca / Mexico Posts: 7,874	.............hehe your in for some fun. i just finished doin this swap in my 3/4 ton.Things your going to need are the brake brass fitting 3/16 female to 1/4 male(real pain to find so i incountered). Oh and the U-joint strap kit i used was "360-10" napa. Last edited by Alexis; 12-11-2002 at 07:58 PM.

12-11-2002, 07:59 PM	#4
Alexis Member since 2000 Join Date: Dec 2000 Location: Mountain View Ca / Mexico Posts: 7,874	hers a picture 14-bolt FF 4.56 posi Attached Images

12-11-2002, 08:00 PM	#5
Alexis Member since 2000 Join Date: Dec 2000 Location: Mountain View Ca / Mexico Posts: 7,874	picture of the fittings kinda blurry cause i used the program to zoom Attached Images

12-11-2002, 09:35 PM	#7
jerry moss Born Psycho Join Date: Feb 2001 Location: brentwood,cal,usa Posts: 4,946	i've done this swap on a few trucks, it takes some time but is well worth the effort. you can buy new spring pads at most speed shops, i use a 4inch grinder to cut off the old pads. grind off and re-use the shock mounts (they're staggered on the 79). you'll need an angle guage to set pinion angle, brake line fittings and longer e-brake cables. i get my e-brake cables redone at nevada speedometer in reno nevada. if you have any questions, feel free to call me, 925-634-2512. __________________ jerry moss 72 cheyenne super K20- tilt,tach,vacuum,speedwarning,buckets,shoulder belts,am/fm,tow hooks,bumper guards,toolbox,aux. fuel tank,posi front and rear,plus other goodies!!! SOLD 69 suburban K20-tilt,tach,vacuum,speedwarning,buckets,shoulder belts,am/fm,4 inch all spring lift,4 speed, 14 bolt full floater, dana 44 HD,warn winch,posi front and rear,tow hooks,plus other goodies. 73/80 chevy/gmc K20 SB400,turbo 400,205,tilt,a-c,gas hog. 77 K/5 cheyenne blazer-daily driver/beater. SON HAS IT NOW BRENTWOOD,CALIFORNIA

12-11-2002, 07:40 PM	#2
ozarkhippie Registered User Join Date: Nov 2002 Location: Eureka Springs AR Posts: 494	measure the distance from center to center of the spring perches of each axle. If the 14 bolt came out of a 1 ton it should be the same as the one in your 70, so there should not be any spring perch relocation.

12-11-2002, 09:00 PM	#6
4x4 Pray Registered User Join Date: Apr 2001 Location: San Luis Obispo, CA Posts: 69	thanks for the tips. went and measured my perches and the new perches. mine are about 2.5" narrower. guess the 14 bolt is from a 3/4 ton then. thanks for the pics too. you looking good. mines covered in rust.

12-11-2002, 10:45 PM	#8
4x4 Pray Registered User Join Date: Apr 2001 Location: San Luis Obispo, CA Posts: 69	925? WOW, you live right by me! I go to school in San Luis Obispo, but my hometown is in Clayton (right by Concord). That's pretty cool. Anyway, I appreciate the encouragement. You have inspired me to keep on going on this project. But what's an angle guage look like? And can I set the angle some other way rather than buying the guage? Will it screw things up if just I try to get it as close as I can?

12-11-2002, 11:20 PM	#9
roger0080 Registered User Join Date: Nov 2000 Location: Carver County, Minnesota, USA Posts: 626	I've done this to my 71 K20 also. I'ld rather have the Eaton myself and just pay for the NoSpin diff if you want a locker that bad. You can get a disk brake conversion kit for the Eaton rear end too! Check out: http://members.aol.com/blackbirdstrucks/index4.html But what I did as others said is you will have to move the spring perches in. I had a shop do mine. Relocate the shock brackets on the axle, my pinion strap to the yoke and U-joint fit right into the 14-bolt, did a brake job on the 14-bolt since you have it out. The Eaton uses 5/16" brake line to the wheel cylinders where the 14-bolt will use 3/16". No problem. I bought new wheel cylinders for the Eaton and bolted them into the 14-bolt. Ran new 5/16" line from the wheel cylinders to the "T" connection. No fuss no mess. Hardest part is getting the right pinion angle when it's all done. I had to use some tapered shims and it was pretty close. -Roger __________________ 72 Chev C-10 90% restored (former AZ truck) ... 71 Chev K-20 Cheyenne my vacation crusier... 72 Chev C-10 Now retired and striped after many faithful miles... 72 GMC 1500 Retired to the junk yard after bought new in '71...



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.