K20-K10 Disc swap - The 1947 - Present Chevrolet & GMC Truck Message Board Network

BurnoutNova · 04-21-2004, 01:33 AM

i have a 69 k20, with drums and the knuckle less dana 44, and i have a 71 k10 with the regular 44.

is it possible to take the disc brakes off the 71 and put them onto the 69, and then take the 69's druma and put them on the 71 so it still has brakes? of are the 3/4 and 1/2 toms brakes much diffrent?

1969 GMC · 04-21-2004, 02:44 AM

you won't be able to do this. the trucks both have dana 44 front axles, but the '69 will have closed knuckle axles with the drum brakes. the '71 will have open knuckles with discs. the only thing the axles share in common are the centersection and the axletubes, everything else is different between the 2.

one alternative would be to swap the whole axle from the K10 into the K20, and either swap some 8 lug hubs onto it, or just leave it alone.

or, you could just go to the junkyard and find a dana 44 from a '71-'80 (i think) GM fullsize, which would be the easiest swap. you could keep the gears you have now, and its prett y much a bolt in. (there might be some brake issues).

**JIMs70GMC** · 04-21-2004, 06:06 AM

Some time in the 70s the banjo fitting was changed from standard to metric. You just need to know so you can order the correct brakelines for which ever caliper you have.

**breeh** · 04-21-2004, 10:29 AM

Not all of the 69's were closed knuckle. It was a transition year.

1969 GMC · 04-21-2004, 03:05 PM

i was going by pics of his K/20 that he posted a while back.

however, the '70 axle (with open knuckles and drum brakes) can be converted to discs.

**breeh** · 04-21-2004, 05:23 PM

Oops, I didn't see those pictures. I just didn't want him tossing a good open knuckle D44 based on the year!

BurnoutNova · 04-22-2004, 12:38 AM

yes the K-20 does have closed knuckles...is this stronger than open??? why do they do this?

i think i'll just leave the thing alone, and sell my 71 as is.

it for sale! 2200$ 71 K-10 runs/drives great...needs rockers and corners and doors and fenders, but comes with everything besides one door. the box is good. its got tons of options, posi, heavy springs, etc.

1969 GMC · 04-22-2004, 01:03 AM

closed knuckles are actually weaker than open knuckles. the ujoint inside the "ball" is actually a lot smaller than the ujoint on a comparable open knuckle axle. also, open knuckles axles will give a better turning radius.

the only advantage i can think of closed knuckles is that mud and crap cant get inside the axle tube, like how it can on an open knuckle axle. however, that is negligible when compared to their other disadvantages.

04-21-2004, 01:33 AM	#1
BurnoutNova Registered User Join Date: Mar 2004 Location: CA Posts: 2,057	K20-K10 Disc swap i have a 69 k20, with drums and the knuckle less dana 44, and i have a 71 k10 with the regular 44. is it possible to take the disc brakes off the 71 and put them onto the 69, and then take the 69's druma and put them on the 71 so it still has brakes? of are the 3/4 and 1/2 toms brakes much diffrent?

04-21-2004, 02:44 AM	#2
1969 GMC Registered User Join Date: Feb 2003 Location: The Rubber City Posts: 5,498	you won't be able to do this. the trucks both have dana 44 front axles, but the '69 will have closed knuckle axles with the drum brakes. the '71 will have open knuckles with discs. the only thing the axles share in common are the centersection and the axletubes, everything else is different between the 2. one alternative would be to swap the whole axle from the K10 into the K20, and either swap some 8 lug hubs onto it, or just leave it alone. or, you could just go to the junkyard and find a dana 44 from a '71-'80 (i think) GM fullsize, which would be the easiest swap. you could keep the gears you have now, and its prett y much a bolt in. (there might be some brake issues). __________________ 1969 GMC K2500 1996 Honda Accord 2007 Kawasaki KLR 650

04-21-2004, 06:06 AM	#3
JIMs70GMC user # 2756 Join Date: Jun 2001 Location: Chesapeake, Virginia Posts: 4,612	Some time in the 70s the banjo fitting was changed from standard to metric. You just need to know so you can order the correct brakelines for which ever caliper you have. __________________ 1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs 1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX 1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears 1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now..... 1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone. 1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed. 1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm

04-21-2004, 10:29 AM	#4
breeh Recovering 67-72 Addict Join Date: Oct 2000 Location: North Bend, WA Posts: 1,788	Not all of the 69's were closed knuckle. It was a transition year. __________________ 68 Short Fleet 4x4; 427; BTO Level 3 700R4; NP205; Dana 60 front and rear; 4" lift with 35's; Disc brakes; AGR variable ratio steering; factory bucket seats; factory tach and tilt. "Friends call me cruzer cuz I like fast cars and fast women"

04-21-2004, 03:05 PM	#5
1969 GMC Registered User Join Date: Feb 2003 Location: The Rubber City Posts: 5,498	i was going by pics of his K/20 that he posted a while back. however, the '70 axle (with open knuckles and drum brakes) can be converted to discs. __________________ 1969 GMC K2500 1996 Honda Accord 2007 Kawasaki KLR 650

04-21-2004, 05:23 PM	#6
breeh Recovering 67-72 Addict Join Date: Oct 2000 Location: North Bend, WA Posts: 1,788	Oops, I didn't see those pictures. I just didn't want him tossing a good open knuckle D44 based on the year! __________________ 68 Short Fleet 4x4; 427; BTO Level 3 700R4; NP205; Dana 60 front and rear; 4" lift with 35's; Disc brakes; AGR variable ratio steering; factory bucket seats; factory tach and tilt. "Friends call me cruzer cuz I like fast cars and fast women"

04-22-2004, 12:38 AM	#7
BurnoutNova Registered User Join Date: Mar 2004 Location: CA Posts: 2,057	yes the K-20 does have closed knuckles...is this stronger than open??? why do they do this? i think i'll just leave the thing alone, and sell my 71 as is. it for sale! 2200$ 71 K-10 runs/drives great...needs rockers and corners and doors and fenders, but comes with everything besides one door. the box is good. its got tons of options, posi, heavy springs, etc.

04-22-2004, 01:03 AM	#8
1969 GMC Registered User Join Date: Feb 2003 Location: The Rubber City Posts: 5,498	closed knuckles are actually weaker than open knuckles. the ujoint inside the "ball" is actually a lot smaller than the ujoint on a comparable open knuckle axle. also, open knuckles axles will give a better turning radius. the only advantage i can think of closed knuckles is that mud and crap cant get inside the axle tube, like how it can on an open knuckle axle. however, that is negligible when compared to their other disadvantages. __________________ 1969 GMC K2500 1996 Honda Accord 2007 Kawasaki KLR 650

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.