92 chevy axle and front end in a 68 GMC???

[lts70]

My dad has a 1992 Chevy half-ton donor truck with the five lug set up. He wants to put the rear axle and front end on his 68 GMC. The 68 is a 2wd heavy half ton with 6lugs in the front and 8lug leaf springs in the back. If I remember right you can run the 92 front spindles on the 68’s stock A-arms with changing out the ball joints and a few other things. And I would think the rear end would work were it is a leaf spring setup on the 68.
So I have a few questions for you guys.

1) Does anyone know exactly what you have to do (or have a link) to the stock front end to run the newer spindles and disc brake set up off of the 92 on the 68?

2) Could I use a drop spindle for a 92 on this set up?

3) Would the 92 rear axle work pretty good for this application, length, strength, clearance, etc.?

4) What is the best way to drop a ¾” ton leaf set up? Flip kit?

Thanks for any help or advice. I am trying to get a plan together of parts needed so I can start cruising up to Idaho on the weekend and help my dad build his dream truck. I just want to have it all ironed out before I go up to help so that my time is spent working and not scratching my head.

Last time we worked on his truck we got it tore down to a rolling frame. But demo is the easy part

[chevy_mike]

Yeah, I remember that thread but I can't find it either. It was originally in the 60-66 forum. I was smart enough to copy the info so I can give you that. You do need a lower 3/4 ton a-arm AND ball joint from a 67-72 truck/van. You use the stock upper arm BUT use the '92-'98 ball joint (assuming you are using this year spindle, the 88-91 had a light duty and heavy duty option and you would need the HD version). Here's the info I copied.

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

I actually bought a set of spindles and was going to do this on my '64 I had but sold it, bought the '68 and went with ECE full suspension and brake setup.

Hope that helps.

[chevy_mike]

Oh, as a follow up, you needed to do something different for the tie rods but I forgot to copy that. To answer the question about dropped spindles, yes you could use the late model ones, for the same years as you would stockers.

As for the rear end, I don't think using the 8 lug would be the best, especially if you are using 5 or 6 lug in the front.

BTW, using the late model stuff, you can use the 1/2 ton 5 lug or 3/4 ton Light Duty rotors for 6 lug. Swap rotors and you can swap the lug pattern easily.

[MickMc]

Outer tie rods from the 92 and adjuster sleeves...
Inner tie rods # ES2020RL



I guess I had better hurry up and finish my brake conversion write up...




Mick

[lts70]

Thanks chevy_mike - so will a 1992 1500 2wd work? Or does it have to be HD version to work at all? How can I find out if it is HD? It had the 4.3 V6 and a NV3500 tranny. It is a single cab long bed. I don't plan on using the 8lug, I would like to run the 92's rear axle as well if it will work.

What is the difference between a 3/4 ton and 1/2 ton lower A-arm?


MickMc- If you had a write up that would be great.

The 92 has 600 miles on it from the factory so if it is the right truck for this swap I will pull the ball joints,Outer tie rods,adjuster sleeves, and any thing else right off of the 92.

[MickMc]

[QUOTE=lts70;3110090]Thanks chevy_mike - so will a 1992 1500 2wd work? Yes, but do you want 5 lug or 6 lug.Or does it have to be HD version to work at all? The 7200 gvw will get yu the 6 lug rotors, all others are 5 lug. How can I find out if it is HD? It had the 4.3 V6 and a NV3500 tranny. It is a single cab long bed. I don't plan on using the 8lug, I would like to run the 92's rear axle as well if it will work.

What is the difference between a 3/4 ton and 1/2 ton lower A-arm? 3/4 lower control arms have a larger hole, for a larger ball joint. The 88-98 lower ball joints will fit in a 67-? 3/4 ton lower a-arm. With the 88-98 lower ball joint pressed into the 3/4 ton a-arm the 88-98 spindle will bolt right up.
Next you need the 88-98 upper ball joints installed on you stock upper a-arms.
You must use the 3/4 ton lower a-arms, NO MATTER WHAT, if you are converting to 5 lug of 6 lug using the 88-98 spindles.

MickMc- If you had a write up that would be great. I have the draft completed, I'm just trying to figure out how to add photos, to make it a little more self explantatory.

The 92 has 600 miles on it from the factory so if it is the right truck for this swap I will pull the ball joints,Outer tie rods,adjuster sleeves, and any thing else right off of the 92.
If this truck has the right lug patten you want (5 lug or 6 lug) you're almost home. Just pull spindles out, plus the tie rods and adjusters. Next find lower 3/4 a-arms and buy new upper and lower ball joints and you're done.[/QUOTE]


Chevy Mike, thanks for the cross over data. I want to use it in my brake conversion write up.


Mick

[lts70]

MickMc- Thanks a ton for the info, that is exactly what I needed to know. Do you see any problem with using the used (600 Miles) ball joints out of the 92 instead of buying new ones? The 92 has 5lug and that is what I want to use on the 68. That way I can use the 92's rear axle as well to have a 5lug truck all the way around.

Has any one used a rear axle out of a 90's truck on a leaf spring 67-72? I figure I would have to chop of the mounting bracket and weld on the leaf spring perches from the 68. Or is there more to it? Could I do flip kit as well?

I dropped my 70 myself and converted it to 5lug disk brakes but have no experience with leaf spring trucks. Any advice would be appreciated.

[chevy_mike]

MickMc - Glad to help.

lts70 - How in the heck to you have a '92 C1500 with ONLY 600 miles on it? Was it totaled or something. If the truck is in great shape, I would sell it for some $$$ and be money ahead.

As for the rear axle, I don't have any info outside of what you have figured out. Remove all the old brackets and basically get the new axle to match the original one, with the same brackets and such. I don't have the measurement for the newer one but up to '70 the axle measured between the brake backing plates, 57" and '71-'87 was 58.5". See how that compares with the 88-98. If about the same, you should be okay. If wider, you might run into wheel clearence problems.

[MickMc]

600 mile ball joints no problem.
But you are going to have to press out the lower ball joints and then press them back in the 3/4 lower a-arms, with talent and luck and a lot of practice you should be OK. Be careful and take your time.

The rear axle is easy. All you need is new spring perches. I think Moroso has the nice thick ones. Put the pads on the housing and mock everything up, set the pinion angle where you want it and tack the pads. Take everything apart and weld away.



Mick

[lts70]

chevy_mike- the 92 was donated to the College of southern Idaho's Auto school by GM. It was produced with out a title. By the time my dad got it the throttle body was gone among various other small things and the paint was all peeling of from a bad practice paint job at the school. I put the NV3500 tyranny in my 70. Sold the bed to a friend pulled the 4.3 (with out throttle body) and put it in storage for my 68 CJ-5 in the future. Now the front end and axle will go on my dad's 68. So their is basically a frame and cab left


MickMc-When I pressed out the ball joints on my 70 I thought some one had welded them in at first But after finding a good and long cheater bar for the old school press they gave up. After a good sand blasting of the arms the new one went in pretty easy.

[sneakysnake]

Here is a link on doing a 6 lug drum to 6 disc may have some info you can use.
http://67-72chevytrucks.com/vboard/s...t=35042&page=1

[lts70]

Thanks sneakysanke that was the exact thread I was looking for.


Does anyone have a link to some good spring perches?

[chevy_mike]

As MickMc mentioned, Moroso makes some very good ones.

http://store.summitracing.com/partde...5&autoview=sku

[lts70]

Thanks for the link chevy_mike. This site is the best. I left Positive reputation points for you guys.


Has anyone used a brake booster & master cylinder setup off of a 88-98 truck? Is it doable?



.

[chevy_mike]

Sorry no info about the booster and MC. Thanks for the reps.

BTW, I found the link to the original thread regarding the disc swap.

http://67-72chevytrucks.com/vboard/s...ad.php?t=35042

[clay68c10]

The booster/master should work. You'll have to experiment with the pushrod length and mounting to the firewall. The later trucks used a simpler mounting setup to put the booster on the firewall than the 67-72.
It may be easier to use a 67-72 booster & mounting bracket/pushrod assy and put the 92 master on that.
It all depends how much fab/re-engineering you want to do. I do think the later booster setup looks way cleaner.

[lts70]

Thanks again for all the Info guys. I will take a look at the booster and MC set up and see how much fab it will take. If not to bad I will use it. Or mabye I will do as clay68c10 said and use a 67-72 booster & mounting Bracket and pushrod assy and put the 92 master on that. Has any one done that before? Is it a direct bolt on?

Has anyone used a front swaybar off of a 88-98 on our 67-72 trucks?

Or have info or a picture of a 67-72 with a 88-98 booster and MC on it? Or a 88-98 MC on a 67-72 Booster?


.

[lts70]

Well I had my father measure the 92's rear axle and it is 57" from inside flange to inside flange. So if the flange itself is 1/4" steel then rear axle should be around 57-1/2". I believe 67-69 are 57" and 70-72 are 58-1/2" so the rear axle should be the right width. That is good news.

I found some drop spindles at LMC Truck ($290+SH) and eBay($175 Free SH), links below. Do you guys know of any cheaper places to get the drop spindles? The eBay ones are made by Chassis Tech, are they a good brand?


http://www.lmctruck.com/ICATALOG/CD/full.aspx?Page=102

http://cgi.ebay.com/ebaymotors/drop-...QQitemZ3701542

[jbristo67]

Originally Posted by lts70

My dad has a 1992 Chevy half-ton donor truck with the five lug set up. He wants to put the rear axle and front end on his 68 GMC. The 68 is a 2wd heavy half ton with 6lugs in the front and 8lug leaf springs in the back. If I remember right you can run the 92 front spindles on the 68’s stock A-arms with changing out the ball joints and a few other things. And I would think the rear end would work were it is a leaf spring setup on the 68.
So I have a few questions for you guys.

1) Does anyone know exactly what you have to do (or have a link) to the stock front end to run the newer spindles and disc brake set up off of the 92 on the 68?

2) Could I use a drop spindle for a 92 on this set up?

3) Would the 92 rear axle work pretty good for this application, length, strength, clearance, etc.?

4) What is the best way to drop a ¾” ton leaf set up? Flip kit?

Thanks for any help or advice. I am trying to get a plan together of parts needed so I can start cruising up to Idaho on the weekend and help my dad build his dream truck. I just want to have it all ironed out before I go up to help so that my time is spent working and not scratching my head.

Last time we worked on his truck we got it tore down to a rolling frame. But demo is the easy part

it would almost be the same money to buy spindles and run the rotors off of the 92 you can order all the brackets from CPP to weld on to your rear end off the 92 to make it mount up its like a 130 bucks i used 94 rotors on my 67 i think i got spindles that would accept 1 1/4 rotors about 300 dolars and it was a piece of cake

[lts70]

I am still trying to find someone that has info or a picture of a 67-72 with an 88-98 booster and MC on it. Or a 88-98 MC on a 67-72 Booster. Or has used a front sway-bar off of a 88-98 on our 67-72 trucks.

Any help would be appreciated

[Dahawk]

If I use a later model front brake set up on my 67 all i need from the 90 truck is the upper and lower arms to include hardware. Is this switch limited by year of the donor

[sneakysnake]

Originally Posted by Dahawk

If I use a later model front brake set up on my 67 all i need from the 90 truck is the upper and lower arms to include hardware. Is this switch limited by year of the donor

The A arms off a 90 truck wont fit 67 front end.