'80 stepside swb retromod project
 

Well, we finally got around to starting our new project. This is my friends truck and I'm really excited about this project as I'm stepping out of my comfort zone as a GM dealership technician. I've built more than a few custom vehicles, but this will be the first frame off custom build I've been a part of. This truck is a '80 Sierra Grande with 70,000 original miles on it. It has spent it's life in Northern CA and Northern NV, and as we found out today that is really really cool. We only had to cut off one bolt, and that was because it had been removed in the past and someone put some really nasty loctite on it. Virtually no rust on this thing, and the PO's only did a few "stupid" modifications. The plan is to strip and paint the frame, rebuild all the suspension and add a 4/5" drop, install a 6.0 ls2/6l90e combo, maybe regear (no idea what the current gear ratio is) and install a locker in the 12 bolt rear. The body probably won't get a whole lot of attention just yet as he is unsure of the color he wants and the chassis/engine cost is really adding up quickly. Anyone know what the more common gear ratio's used in these 1/2 ton's were? Any other advice and tips will also be greatly appreciated.

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We removed the really awesome shell last weekend. Someone actually wanted it and came to get it yesterday. Day 1 of the teardown consisted of removing the bed, and front clip, and removal of the po's wiring jobs. Thankfully they only tapped into a few of the factory wires. May not sound like we got a ton accomplished, but we took everything apart on the front end as we are going to be cleaning and painting it all. I work on vehicles all day long for a living, and I have to say they are not built like they used to be. I was amazed at the amount of hardware we removed. The new cars are all plastic clips and poorly put together. This thing could survive the apocolypse!

We have a garage to work in, but it was a really nice day today and the carport worked out great.

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Forgot to mention, this truck has the 350/350 combo in it.

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Look at the tag in the glovebox for the rpo code on gear ratio. I was surprised to find that my had 2.76 gears from the factory with a 350/350 and a 12 bolt.

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Tried that, tag is not there. Probably will just have to find out the old fashioned way. I'd suspect this truck has very high gears in it as well, the engine did not sound like it was spinning fast going down the highway at 70 mph.

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nice truck/wish mine was that clean when i started. check out the hotrod magazine roadkill muscle truck on youtube they got an ls motor turbo 400 trans gear vendors overdrive ford nine inch rear end with 513 gears 4 inch exhaust man that thing screams.-jeff

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Ya, we got lucky on this truck. It's actually the first one we went to look at. Most of them on craigslist were pieced together, were just junk, or were already done. I think this one was in the parts section of craigslist and was listed as "truck". My friend had been looking to do this project for a while now and after seeing this truck in person I told him "if your serious about doing this project buy this truck!"

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It arrived. 2012 6.0 l96/6l90e. Won't be able to unwrap it until Sunday.

Re: '80 stepside swb retromod project
 

Day 2 teardown progress. Did not get as far as we had hoped. Cab is unbolted, just need some help to remove it. Got the ls2 separated from the trans, and it's getting prepped for paint, I'll be working on the harness this week. I got a lot of grief for how I decided to hook up the chain to the old engine..... I kept telling him that if it falls were not out much.

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Oh ya, pulled the rear diff cover. 2.70 gears.... Gonna go 3.42's.

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The truck has a 12 bolt and I am going to regear it and add a posi diff carrier (probably an auburn). What are your thoughts on c clip eliminators?

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They often leak, and I would go to a 9 inch if I had to get rid of them. I did it to a 10 bolt I had, and played hell having to fix the leak.

I heard someone makes weld on 9 inch end, and if that is true then I would do it.

C-clips are fine to a point, and unless you race alot they are fine. Just get good axles.

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Is anyone running 325/50/15's, or 28x12x15's on 10" wheels? If you are, can you post a link or a picture of that combo on your truck? Trying to decide whether to go with 295's or 325's. Thank you.

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Found a pic.

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I cant understand why they put 3 blade fan on these trucks. My 82 3/4 ton has a 3 blade also.

Good looking truck by the way. Clean also.

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BTW. There is a code stamped on the axle tube. You can call the chevy dealership and they can look up the code and tell which gears were installed from factory. Find mine on passenger side top by the brakes.

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Day 3 work. Not as much done as expected again. Took a lot longer to get the chassis stripped than originally thought. We had a little trouble with getting the cab off of the chassis, should have went with the original plan and just got some extra hands to help lift it off. The way we did it was ok, just took much longer. We looked for a steam cleaner to rent, but no one around here rents them any more, so we rented a 3500 psi pressure washer to clean the chassis and it did a very good job. Now we just have to make a couple repairs on the rear of the chassis, remove a couple unnessessary mounts, clean it a bit more and paint it. I think we finally decided on tire size, so that's a plus. 15x10's with 295/50's in the rear. Gonna go with a 2.5/4" drop to start and see how it looks.

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more, not sure why, but I have the hardest time loading pic's. I get one uploaded then get connection error messages. Only happens on this site.


After 2 1/2 hours of pressure washing.

Re: '80 stepside swb retromod project
 

Kind of a weird question, but is this the company that manufactures S&P headers? Thinking about ordering a set from them, and having them program the ecm. Any thoughts on the matter?
http://www.hotrodlane.cc/

Re: '80 stepside swb retromod project
 

Great looking truck and great engine trans combo. I wish my truck was a clean as yours when I started.

That is S&P performance site. It has a lot of good info but is a terrible designed site. I dont have any experience working with them though.

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I just wanted to make sure it was them. The site is horrible, and the online catalog is worse. I called them the other day and they were very friendly and helpful. I'll end up calling them again to order the headers and to get the info on sending in the ECM. Thank you

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Tires..... Got the size figured out, need thoughts on brands. Cooper cobras or bfg ta's?

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Got some work done today. Had to trailer it into work to use the welder to repair the frame. Don't make too much fun of the welds, its been a while, and I'm not a welder... Anyway, the previous owner had welded something to the bottom of the frame, then torched it off, leaving some holes and the bottom of the frame was questionable so we repaired it. The rear upper shock mounts in the frame were both really badly opened up due to the mounts working loose, so I welded in some grade 8 washers on both sides of the frame to repair it. Then I checked out the the steering gear area of the frame and found a small crack, so I welded that up as well. Next, we cut off the rivets on the rear spring shackles and replaced them with bolts. We plan on lowering it with shackles, and since we were at work I figured I't knock the rivets off real quick with my air hammer verses cutting them off with a cutoff wheel at home. Also took the factory exhaust hanger off of the frame. Now its finally ready for sanding and paint.