70 vs 85 chev questions

[onetoncrewcab]

Got a couple of questions on a transplant I want to do on my 70 Chev 1/2 ton pickup. I have the 6 bolt pattern rims on it now and want to change to 5 bolt. I have an 85 chevy Suburban that I can get the whole drive train out of it. I know the engine cradle with the disk brakes is a bolt in operation. Not a problem. Here are my questions:

What about the rear axles? Can I remove these from the sub and bolt them in on the 70? I think I read that the 73-80 axles are bolt in. What is the differance at 85? If the bolt in is a probem, I can get new brackets to weld to the 85 axle and do the transplant that way.

Will the power brake booster work on the 70? From what I've understood, I'll probably have to fabricate a new linkage from the pedal to the booster.

What about the power steering gear. This is probably metric, but if I use the power steering pump setup from the same truck, it should work?

The sub I'm using is a fairly decent truck with a rebuilt engine and trans. I don't want to use it for a parts truck if all I can use is the engine cradle though.

Thanks for the help!
Mike

[Hardrock2]

Hey there,
Swapping to late model 5-lug suspension is kind of a mixed bag.
The '85 'burb should have the Corp 10-bolt rearend, not the "good" old 12-bolt that's in your '70 now. Best bet is to use
the axles from a '71-'79 truck. They still used the 12-bolt rear,
in the same width as your '70. Easy swap.
As far as the front cradle goes, it's a drop-in, with only 2 holes to re-drill, and some brake line juggling. BUT......most '81-'87 1/2 tons (and subs) have the thin disc rotors, and , I believe smaller wheel bearings. (?) Again, the best bet is a '71-'79
cradle with the beefy rotors. better yet is the '73-'79 set-up that gives you the big rotors, and the rubber bushed A-arms. '71-'72 A-arms are the old "harsh" metal bushings. Going with the '73-'79 style makes it easier to upgrade to urethane bushings, also.
As for P.S. boxes, that's where the '81-'87 trucks shine! Better chance finding a lower mileage unit, quicker ratio, AND.....O-ring (metric) fittings. Works well with most late model engine swaps when using the late style pumps. Usually all that is needed is a new high pressure line that's o-ringed on both ends. Almost always in stock at the local parts house!

Might check a recent post by 73stepside.......similar topic.
Hope this helps!
Mike

[onetoncrewcab]

Arrrrgh! I say as I pull my hair out. LOL Here is my dilema:

I have three choices so far:

1. I found a mid 70's pickup with a rebuilt trans that has all the suspension parts and rear axle parts I need. I would need to come up with an engine for project though. The guy will take $300 for the truck and it has been sitting for around 6 years so I am not sure how good the trans is anymore.

2. I found a mid 70 suburban without an engine or transmission. The guy wants $300 for it, but I was going to offer $100. Again, this would have all the suspension and rear axle parts I would need. But I'd still have to come up with an engine and transmission.

Either option above means finding at least an engine.

3. I have an 85 Suburban that is complete. It has a rebuilt engine and 700R4 trans in it. This would have all the parts I need, but I would have to weld new brackets onto the rear axle to get it to mount under the 70. The width was about a 1/2" wider or so.

I also have a 454 and a Turbo 400 trans in a 1982 crewcab for the engine/trans for option 1 or 2. I could buy the mid 70s sub and have all the parts I need. I'm not sure I want the 454 in the truck as I'd like something that doesn't use quite so much gas.

I could also use the engine and trans out of the 85 and sell the rest of the truck for whatever I could get out of it. It has power windows/locks and is in fairly decent shape.

I tried to sell the 85 Sub a couple of years ago for around $1700. But I would have taken any offers around $1200. I just don't want to spend money on a bunch more parts trucks and then can't get my Suburban sold for a decent amount.

ANY SUGGESTIONS???
Thanks
Mike

[Hardrock2]

Boy, I sure hate to see a decent 'burb sacrificed! They make great parts chasers!! But, it looks like you have a spare one!
LOL!! Making the brackets to mount the 10-bolt 'burb rearend wouldn't be too hard.....but you'll still have a 10-bolt. (they are also slightly shorter from the axle centerline to the pinion flange, than the 12-bolt) That would mean you may not be able to use your original '70 driveshaft. Just a thought. Buying the '70's 'burb for the 5-lug disc cradle, PB booster, lines, prop. valve, etc, and rear axles/brakes and running the 454 and TH400 you already have sounds good to me. Especially since there's bound to be some usable parts from it that can find their way onto the '85, if needed! If they are setup right, 454's aren't all that bad on gas. Too bad you couldn't swap the TH400 into the '85 'burb and use the fresh 700R4!! Sounds like alot of work, but you would still have a sellable suburban in the end! And not alot of $$$ spent!
Also, that extra 'burb rear tank could be used to rid the '70 of the dreaded in-cab gas tank!


BTW, Wierd enough, I've been thinking about a new project involving a K-30 rolling chassis............what are you asking for the '82 rolling?

Mike

[onetoncrewcab]

Hardrock,
I'd take $600 for the 82 less the motor, trans and tilt wheel column. The chassis has the Dana 44 3/4 ton front axle and not the Dana 60. The ball joints were replaced on the right side a couple of years ago. I also had the long side of the tie rod replaced at that time. The rear axle is a 14 bolt. I'm not sure if the two axle ratios are the same tho as the front axle was a replacement. The tires are Trail Mark APR LT 285/75R16 with about 50% of the tread left. THese are around 31" tall. The brakes have just been redone up front with a new rotor on the left side. There is a NP205 transfer case that has been rebuilt, but it started jumping out of low range about a year ago. The seats are power bucket seats from a Lincoln Continental.

I'd take $2000 for the complete truck, but the body is shot. I'm not sure there is a usuable panel on the thing.

Right now I'm leaning to buying the mid 70s Suburban if I can get it for $100 and then take the engine and trans from the 85 Sub since both of them are rebuilt. 2 wheel drive Subs just don't sell well in this area. I had it on the market for 4 months and only got three calls and no lookers. I figure if I end up putting a used engine in my 70 that I need to rebuild later (for upwards of $700-$1000), I think I'm better off using a rebuilt engine from a truck I'd only get $1000 from anyway.
Decisions decisions.

Thanks for the reply. Drop me a line if you are interested in the crewcab.
Mike

[Hardrock2]

I was thinking about building a'72 K-30 dually, but the D60 front is the "most needed" piece. $600 doesn't sound like a bad price, though! Around here decent suburbans bring a fair price with the racers and campers. I looked for awhile till I found a good price on a pair of'em. One drove, the other, I had to haul, but it had a low time engine in it.(bad trans.) A week of evenings swapping stuff around, and I had a fairly decent "parts chaser/ tow rig"
They were both 6.2L diesels, so I don't worry too much about fuel milage!
Sounds like maybe using the 'burb engine/trans. might be a better route to go if you know its history pretty well.
A place to go with the 2 suburban remains might be www.ColoradoK-5.com . They have a forum just for the subs.
Usually a fair amount of parts sold there. Shoot, I might be interested in a good pair of rear barn doors for mine, but the shipping might be a tad high from there to here
Hope it all works out well!

Mike

Oh, BTW here's my '85

[68 Stepside]

I would definitely try to use the rebuilt engine/drivetrain if at all possible. I think you've got a good plan going, use the drivetrain you have, and buy the cheapest vehicle you can find to swap parts off of.

Central Illinois hardrock? Let me give you a very late welcome to the site, from a "former" central Illinoisan. I just moved out here last year...I don't miss the snow at all yet....

[Longhorn Man]

TJ, after a few years, you'll miss playing in the snow.
No body in the south gets the 'yellow' snow jokes.

[68 Stepside]

LOL

I must say....I did miss riding a snowmobile this winter...I didn't miss rolling at 100 MPH, but I did miss riding one in an upright manner

[Hardrock2]

Howdy TJ, thanks for the welcome! Not much changes in good 'ol IL. Crops in the summer, snow drifts in the winter! (and SALT) LOL!
What part of IL did you move from? I'm just about 30 mi. N of Effingham. On lake Shelby.

Mike

[68 Stepside]

You're in a nice part of the state. I lived in a little town called Gridley, it sits in between I55 and I39. About 20 miles north of Bloomington/Normal. Now that I've gotten rid of the wintertime salt, I have sea salt to deal with...LOL

[Hardrock2]

LOL!
At least when the tops rust off down there, you have convertible weather!
Up here, when the floors rust out, we don't have a season for that!

Mike