Rear end Questions

[softballnrd27]

I have a 85 that will eventually be a street/strip machine with more emphasis on the strip but I still want to be able to drive it on the street occasionally. I am thinking 9" rear but don't know what to use for the carrier. Spool or locker? If locker, detroit the best? I owned a Rockcrawler with a detroit and it was bulletproof, are they just as good for the strip?

[team39763]

I run a Eaton limited slip(clutch type posi). I heard the Detroit locker is nearly bulletproof, but a bit aggressive for the street. The Detroit Tru-track(sp?) is nice but doesn't stand up to much abuse from what I've read and isn't rebuildable like the Eaton unit. My truck doesn't make much power and it isn't really fast, but it has been put through the abuse of drag racing with slicks. So far I haven't had any problems with the Eaton unit. Many of the new body style truck guys choose the Eaton also. I had one in my NBS truck(2000 Sierra) that took a bunch of abuse and it worked flawless.

[68GMCCustom]

You don't want to run a spool on a street/strip truck.
Strip only - run the spool.

[Captainfab]

I would go with the Detroit. As already mentioned they are a little aggressive on the street, but if you've been into rockcrawling you already know what they're like

[softballnrd27]

I have dealt with the detroit before and it wasn't bad once you learned what it was going to do. I got a guy that I work with that has a low 11 sec Malibu that he races and he runs a detroit in a 9" with a 5spd and a nitrous big block. Now I just need to find out how wide I need my readend so I can find a housing for it. Next decision, trailing arm rear suspension or caltrac and leaves.

[ripdog28]

I love my locker, even when sideways itll go straight and not spin out if youcan drive of course. Not to annoying because the motor is louder then the locker when turning.

[djracer]

If you run after market axles and a spool you can drive it on the street a little. The detroit is really expensive and will still be locked most of the time. I would probably run caltracs if I was already leaf. With that said I am changing my son's 70 model to a trailing arm coilover setup.

[softballnrd27]

I am going to get the suspension right before I do a real motor and I am really leaning towards the trailing arm system. I love the way your truck hooks DJ and that has me sold on the trailing arm suspension.

[softballnrd27]

When going 9", can I get a housing from the junkyard and add some bracing and be good or do I need to go aftermarket like currie or moser?

[djracer]

You can do a stock housing with bracing. That is what I just took out of my truck for a fab housing. I am gonna put my old one in my son's truck.

[68GMCCustom]

Originally Posted by djracer

If you run after market axles and a spool you can drive it on the street a little. The detroit is really expensive and will still be locked most of the time. I would probably run caltracs if I was already leaf. With that said I am changing my son's 70 model to a trailing arm coilover setup.

was it a leaf spring truck?

[Captainfab]

An '85 would be leafs........

Originally Posted by 68GMCCustom

was it a leaf spring truck?

[68GMCCustom]

LOL...I guess so! I missed the year I guess.

[ripdog28]

IMO, stay leaf w/cal tracks. It would be easier to just go 4link if you wanted to get rid of the leafs.

[djracer]

Originally Posted by 68GMCCustom

was it a leaf spring truck?

Your truck should have come leaf if it didn't have coil spring rear as an option.

My son's 70 model is a chevrolet but it came with the leaf option.

[softballnrd27]

It has leaf springs in the rear but I like the trailing arm suspension. I haven't made up my mind yet on which way to go.

[68GMCCustom]

Originally Posted by djracer

Your truck should have come leaf if it didn't have coil spring rear as an option.

My son's 70 model is a chevrolet but it came with the leaf option.

y'all will notice a couple of differences between the frames...that make the swap a little bit of a pain....lots of rivets to deal with to remove the leaf stuff and install the coil stuff.

[djracer]

I didn't have much trouble swapping my uncle 66 gmc. An 85 would be a tougher swap.

[Captainfab]

Seems to me someone was working on a trailing arm/coil conversion for the squarebodies......might have been Porterbuilt?

Originally Posted by djracer

I didn't have much trouble swapping my uncle 66 gmc. An 85 would be a tougher swap.

[djracer]

Somebody does have a kit for the square trucks but I don't remember who.

[softballnrd27]

CPP has a kit but it is $1700 dollars

[68 C-10 KID]

I Have the CCP cross member I took it out and went Porter built and will never look back. It allowed me to have a fully adjustable trailing arm suspension and the ability to run my 5" aluminum drive shaft.

[chris mc bride]

First you can run a spool on street as long as it just a saturday night specail or for rod runs.The only problem you will have is when turning slowly you will feel a little chatter in the tires.It just takes a little getting use to.
As for the hight priced after market housings.unless your going big on the power I would worry about them.You can either buy a junk yard unit shorten it your self,if you have decent fabricating skills(do some research there are tons of articles on it).Once you have new ends welded in you will be good to go.If you want you can spend some time very little money and fabricate some bracing across the back just like the high price units.
I know it sounds like a lot of work.It is but you get lots of rewards.Pride that you built it is number one. Probaly a few comment about it and more satistfaction of sayinf yea I did it my self.Plus you have more money to build more power to see if you can break what you built. Yea but you always push for more,beleive me 25 years of playing with this $hit has shown me this.

[dbmx66]

if your gonna run a spool, youll need after market performance axles and c-clip elimnators.