dream68 can you elaborate on the 88 truck you got the parts off of. Was it a 1/2 ton or 6 lug 3/4 ton? I have Hollanders on my laptop and would be able to post some info for folks. Hollanders does show the 67-70 vs 71-87 3/4 ton lower control arms being different. Which did you use? I have heard you could use the 88-91 3/4 ton 2wd 6-lug rotors on 71-up spindles using 71-up calipers. I went to Autozone and had them pull a 71 1/2 ton 5-lug rotor and a 88 3/4 ton six lug rotor and they were basically the same and appeared to use the same bearing.

JJR: it was a 88 1/2 ton chev 2wd that all these parts came from. everything was ripped off the same truck, even the gearbox, but the gearbox will not fit...

Hollanders shows two spindles used on an 88 c1500 2wd. One for a 1" rotor and one for a 1 1/4" rotor. The spindle for the 1" rotor came on 88-91 c1500 and had a 1 1/4" inner bearing surface diameter. The spindle for the 1 1/4" rotor(which is probably what you have) came on the following:
CHEVROLET PICKUP TRUCK 88 2500 Series; 4x2
CHEVROLET PICKUP TRUCK 88-91 1500 Series; 4x2, 1-1/4" thick rotor
CHEVROLET PICKUP TRUCK 89-91 2500 Series; VIN models "C/K", 4x2, 6 bolt wheel
CHEVROLET PICKUP TRUCK 92-98 1500 Series; 4x2
CHEVROLET PICKUP TRUCK 92-98 2500 Series; 4x2, 6 bolt wheel
CHEVROLET PICKUP TRUCK 99 1500 Series; exc. Silverado; 4x2
CHEVROLET VAN 96-99 1500 Series
CHEVROLET VAN 96-99 2500 Series; 7300 lb. GVW
GMC PICKUP TRUCK 88 2500 Series; VIN models "C/K", 4x2
GMC PICKUP TRUCK 88-91 1500 Series; 4x2, 1-1/4" thick rotor
GMC PICKUP TRUCK 89-91 2500 Series; VIN models "C/K", 4x2, 6 bolt wheel
GMC PICKUP TRUCK 92-98 1500 Series; 4x2
GMC PICKUP TRUCK 92-98 2500 Series; 4x2, 6 bolt wheel
GMC PICKUP TRUCK 99 1500 Series; old style (flat, pull-up outside door handle), 4x2
GMC VAN 96-99 1500 Series
GMC VAN 96-99 2500 Series; 7300 lb. GVW
SUBURBAN 92 1500 Series; 4x2
SUBURBAN 93-96 1500 Series; 4x2, vacuum brake booster
SUBURBAN 97-99 1500 Series; 4x2, gas
TAHOE/YUKON 95-99 4x2

'95 up have ABS sensors on the brake shield.
1-3/8" inner bearing surface dia.
Inner bearing consists of #LM48548 cone & #LM48510 cup.
Heavy duty chassis option code is F44..

15981299 R.
15981298 L.


For lower control arm: the 67-70 3/4 lower arm can come from the following:
CHEVROLET FORWARD CONTROL 68-70 20 Series
CHEVROLET FORWARD CONTROL 68-70 30 Series; 7200 lb. rear axle
CHEVROLET PICKUP TRUCK 67-70 20 Series
CHEVROLET PICKUP TRUCK 67-70 30 Series; 7200 lb. rear axle
CHEVROLET VAN 71 30 Series; drum brake
GMC FORWARD CONTROL 68-70 2500 Series
GMC FORWARD CONTROL 68-70 3500 Series; 7200 lb. rear axle
GMC PICKUP TRUCK 67-70 2500 Series
GMC PICKUP TRUCK 67-70 3500 Series; 7200 lb. rear axle
GMC VAN 71 3500 Series; drum brake
SUBURBAN 67-70 20 Series
SUBURBAN 67-70 2500 Series


If the 71-up 3/4 ton lower control arm can work they can come from the following:
CHEVROLET FORWARD CONTROL 71-72 30 Series; 7200 lb. rear axle
CHEVROLET FORWARD CONTROL 71-89 20 Series
CHEVROLET FORWARD CONTROL 73-78 30 Series; non-removable carrier
CHEVROLET FORWARD CONTROL 79-84 30 Series; drum rear brakes, sgl. rear wheels
CHEVROLET FORWARD CONTROL 85-92 30 Series; exc. hvy. duty front susp.; drum rear brakes, sgl. rear wheels
CHEVROLET FORWARD CONTROL 93 30 Series; exc. hvy. duty front susp.; drum rear brakes, sgl. rear wheels, w/o 9L6 brakes
CHEVROLET PICKUP TRUCK 71-72 30 Series; 7200 lb. rear axle
CHEVROLET PICKUP TRUCK 71-88 20 Series
CHEVROLET PICKUP TRUCK 73-80 30 Series
CHEVROLET PICKUP TRUCK 81-88 30 Series; std. duty susp.
CHEVROLET PICKUP TRUCK 89-91 2500 Series; VIN models "R/V"
CHEVROLET PICKUP TRUCK 89-91 3500 Series; VIN models "R/V", std. duty susp.
CHEVROLET VAN 72-78 30 Series
GMC FORWARD CONTROL 71-72 3500 Series; 7200 lb. rear axle
GMC FORWARD CONTROL 71-89 2500 Series
GMC FORWARD CONTROL 73-78 3500 Series; non-removable carrier
GMC FORWARD CONTROL 79-84 3500 Series; drum rear brakes, sgl. rear wheels
GMC FORWARD CONTROL 85-92 3500 Series; exc. hvy. duty front susp.; drum rear brakes, sgl. rear wheels
GMC FORWARD CONTROL 93 3500 Series; exc. hvy. duty front susp.; drum rear brakes, sgl. rear wheels, w/o 9L6 brakes
GMC PICKUP TRUCK 71-72 3500 Series; 7200 lb. rear axle
GMC PICKUP TRUCK 71-87 2500 Series
GMC PICKUP TRUCK 73-80 3500 Series
GMC PICKUP TRUCK 81-87 3500 Series; std. duty susp.
GMC PICKUP TRUCK 88-91 3500 Series; VIN models "R/V", std. duty susp.
GMC VAN 72-78 3500 Series
SUBURBAN 71-88 20 Series
SUBURBAN 71-91 2500 Series

This statement makes for some confusion: This arm (71-up) may have two different ball joints one being light duty, the other being heavy duty. I am assumming they would be different diameters.

I hope this info helps.

JJR,the info given to me on the 3/4 tons(from local napa) is the ball joints interchange from 71-86 or 87 on the pickups. I didnt see his book, so it was just info given to me. I do know from experience that the 71 3/4 ton lower ball joint will press into the 67-70 3/4 ton lower arms, but the steer stops are different on the older arms(same deal as the 1/2 tons, it will shorten the turning radius), & will require a little grinding on the stops on the spindles to straighten it up.......crazyL

That is good to know Crazy Longhorn. The local pull-a-part tends to have a good selection of 3/4 ton trucks and occationally an 88-up. The get $15 for control arms and spindles. I have also seen several sets of 88-up spindles on e-bay go dirt cheap. People put drop spindles on and basically give away the old ones. Since a already have a set of 71 1/2 ton control arms and spindles and new ball joints for them, I will probably end up buying a set of 6-lug rotors and use what I have.

OK GUYS: the steering linkage is a tad sloppy in the spindle, so this is what you do. use the 68 intermediate shaft with the 88 tie rods. the inside tie rod end is changed to PART# : MOOG ES2020RL.(tie rod end). This setup fits and looks like a dream with no binding anywhere. the 88 tie rods are also bulkier than the 68 original setup..... I will be in touch with more updates as i go... KEEP ON TRUCKIN MAMA!!!!

ALL PARTS NEEDED FOR BRAKE CONVERSION ON 68:::1968 1/2 ton top a-arm, 1970 3/4 ton bottom a-arm, 1988 1/2 ton ball joints(both), 1988 1/2 ton spindles, calipers, and rotors, 1968 1/2 ton intermediate shaft, 1988 1/2 ton tie rods, with the inner tie rod end changed to part#: MOOG ES2020. Brake lines can be changed if need be!!! GET TO WORK!!!

This is great info...but...anyone know if this will work for a 70:confused:

wnc mountain: i believe it should work because the boneyard told me the a-arms were the same from 68-70.

72 to 68 front brake swap
 

New to the group and just saw your conversion. Tell me, i've got a streetable 72 donor truck. Can the front brakes be easily swapped in to a 68? Both are nonpower.

Brake swap to earlier years
 

I've followed this conversation with the understanding that this brake swap would apply for the 60-66. Can you offer your knowledge about this same swap applying to these year Chevys/GMCs?

Application to 60-66 models
 

Will this conversion apply to the 60-66 model Chevys and GMCs. I have a '63 GMC 6 lug that desperately needs more stopping power.

Has anyone else tried this conversion? It seems like a cheap way to add modern brakes to an old truck but I would like to hear from others that have tried it.

Now where to find a set of 3/4 ton lower control arms cheap?

Have you had it on the road yet...?

Was wondering if you felt any difference in the way it handled with the change..?

will the 73-87 stuff work? i've got a 86 frame im gonna be scrapping here in a couple weeks.

You can just put the front crossmember off the 86 on your frame. A search on disc brakes should give you a lot of info on this subject.

i already have discs on my truck...was wondering if it was any use to anyone else.

the 73-87 stuff will not work for this style conversion unless you someone wanted to buy the aftermarket 6 lug rotors...

the 73-87 stuff has 5 lug.

Exactly. Not to mention it is a TOTALLY different swap. Parts used to do the swap are different.

yes, it looks like this... been running it for a while now so it doesn't look as nice but you get the idea. I used a 1990 chevy front end/parts that had 5 lug 1.25" thick rotors and went to AutoZone and bought new factory 6 lug 1.25" thick rotors and bolted them on.
Good luck.

This is probably going to make a lot of disc brake conversion vendors mad :dohh:.

Expect prices to go up on 3/4 ton lower a-arms and the 88 parts, or they will probably package your idea and still sell it for $700-$1000.

All in all, it's really not that cheap. I spent around $400 and I only bought what I had to plus two new rotors. You could easily spend $600 plus if you were buying all new bearings and rebuilding the calipers etc...

The only reason I did this swap was because I wanted to use all parts available at my local AutoZone, O-Riely's, etc. and not have to order special rotors from some company that could go out of business in 5 years.

Hey, FirstGen....

Can you provide any more detail about what exactly parts were necessary for your truck and what you got them off of? I've heard stories of people raiding 1994-1996 Impala/Caprice/Roadsters to get the 5-lug setup.

I am wondering if there is a need to get new a-arms (upper or lower), ball joints, tie rods or intermediate shaft with the method you chose?

I literally have the same truck as you (closer to stock though :D) - I would probably do mine a bit different, just looking for some direction.

TIA