starting mild expo build on 90 GMC Sierra

96discoXD

Adventurer
I decided a while back that I needed a truck to occasionally haul cargo and pull trailers since we replaced my wife's V8 WK Grand Cherokee with a Subaru Forester rated at 1200lbs towing.
I ended up finding a nice solid 1990 GMC regular cab shortbox 4x4 with abour 195,000 well-maintained miles on it. I like the simplicity of the tbi injected small block chevy, 700R4 trans and lever operated transfer case instead of the vacuum/electric setup the later trucks utilize.
So far I've just been doing a few mild things, adding a 2" receiver hitch, some 265/75R16 Sigma Mud Claw tires (more on these later) and doing a new 3" exhaust (a little on the loud side though).
I have a fiberglass Century topper that came with the truck, it sits a little higher than the cab and has a driver's side windoor, but it's also really faded and has a small crack in the top that needs to be fixed. I plan on doing some camping in the truck during hunting season and perhaps later some mountain biking expeditions with my 13-year old son who is getting into it.
I am going to build a nice sleep platform on one side with a wrap around storage compartment in front that will be lockable to provide secure storage for firearms etcetera while at hunting camp. I will also have storage under the sleeping area for camping gear, misc. vehicle spares. The best part is we have some nice mattresses from a set of bunk beds in our storage unit that will work perfect inside the shortbed. I should be able to sleep in the short bed with about 1" to spare between the top of my head and bottom of my feet since I'm a little over 6'3"...
I was going to repair and use the fiberglass topper, but I just found a screaming deal on an ARE DCU topper that looks like it should fit my truck, so I'm hopefully picking that up on Sunday. I already have a Yakima Mega Warrior cargo basket that I should be able to mount nicely on the factory ARE ladder rack and use to carry cargo I don't want in the back of the truck. I will also be adding some Hella 500 off road lights (not that I'll need them too often), but I will fabricate a mounting system that will allow them to pivot backward into the cargo basket when not in use or if wheeling in forested areas during daylight hours.
So far the best mod I have made is the Sigma Mud Claw tires. I agonized over whether to go with an A/T or a M/T, but decided I could live with a little more noise on the road to have better traction in any mud/deep snow situations I might find myself in. I was afraid these tires would hum like boggers, but I have to say they're not much louder than most A/T's I've had before. They are e-load rated so I don't need to worry about overloading the truck for hunting/mountain biking with gear etcetera. The best part is they were only $680 for all four out-the-door at a local tire dealer. Time will tell how they do off road, but they don't seem to really have any negatives on road thus far.
I'll post some pics in the next few days as I hopefully make a little more progress with some more upgrades and mods. I have definitely enjoyed lurking, searching, and reading up on the many fantastic vehicles and ideas others here have executed thus far.:coffeedrink:
 
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Jean-Seb

Adventurer
Sounds like it's gonna be a fun build, I can't wait to see more of it.

I was in the same dilemma about the A/T-M/T choice, but I'll end up doing what you did. Even if the truck sees mostly pavement and gravel right now, the A/Ts won't be good for when the mud comes lol. Might as well have the M/Ts. :D
 

rdraider

Adventurer
I'm in the same boat. I've been thinking about building an offroad teardrop trailer or a slide in camper shell type setup, but can't really afford either. I like the idea of a camper shell: won't be too heavy, allows me to maintain everyday functionality. I have an '08 ford short wide.

You are a little further along than me, i'm still looking for a camper shell, might just break down and build one, not really sure how that will work.

good luck with your project!
 

96discoXD

Adventurer
Jean-Seb, I have seen your truck and the rack you built, it's very nice. I wish I had the skill to weld my own rack, but I took the easy way out and bought one. I'm with you, AT's are probably better for most of the driving I will do, but for that 5% of the time where I find myself in deep mud or snow, I want the peace of mind having an MT.

rdraider, I went back and forth on both of those ideas too, but since I won't be doing any really long-term (greater than 2-5 day) trips with mine for now, I couldn't justify the expense and storage requirements of a trailer or pop up camper in the bed. I think the topper is a great compromise for now, and the good thing is there is always an active market for used ones, so they're easy to sell later if you decide to go another route.

I'll try to post some pics after I hopefully pick up my new topper this weekend.
 

Jean-Seb

Adventurer
Thank you for your comments, I appreciate it. Yeah, I had a few requirements that my rack had to fulfill and I couldn't see that happening with a smaller aftermarket rack, so I had to build to own. Access to a welder at work really helped too...but if I knew it was gonna take me that long to build, I probably would've bought one. lol

Can't wait to see more pictures. :)
 

96discoXD

Adventurer
Here are a few pics I snapped after bringing home my new ARE DCU topper this weekend. I need to repair the ladder rack, which shouldn't be too hard since I have a friend able to TIG weld aluminum. I'll have to make a couple modifications to mount my Yakima Megawarrior cargo rack up there, but it should work pretty well. I just set it up there for the pictures to get an idea what it would look like. I ended up getting the topper for $225, which I think was a steal based on what these seem to go for normally. The extra headroom inside will be great once I get my sleep/cargo storage platform built inside. It does need to slide forward a bit more but I need to do some minor triming to get it in the rest of the way.
My plan is to make a platform as wide as the bunk bed mattress I'll be using and wrap it across in the front. It will have a couple storage compartments with a couple of locks on the forward compartment which I will use to transport my firearms in for hunting. I will leave the other part of the bed open and just put a piece of plywood on the floor to have a smooth floor instead of the bed liner. I plan on insulating the topper with 1" foil-backed foam and then lining it with some gray indoor/outdoor carpet I purchased recently. The sleep/cargo storage platform and panel for the floor will get lined with the same material.
For camp I will use a larger tarp attached to the rack for an awning and I plan to add 1-2 rear work/flood lights as well.
 

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96discoXD

Adventurer
Here's one more showing the side doors open. I'll probably fabricate some sort of screen that I can put in place with these side doors open so I can get lots of ventilation is I'm using it in warmer weather. I will be removing the light inside the topper for now and using some nice little LED lights that I picked up recently for interior lighting.
 

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Rot Box

Explorer
Great start and excellent choice for a pickup :bike_rider:

I've spent more time in these trucks than I could ever count and there are only two major things I've seen problems with aside from idler and pitman arms (those come bad from the factory so they don't count :snorkel:). One is the 700R4 not because its a bad transmission because the gear ratios these trucks came with are usually pretty high and that puts a lot of strain/heat on the transmission. Falling in and out of o/d on the freeway is the number one killer I have seen. One thing I would recommend that's fairly inexpensive is a very large transmission cooler from Summit and a temperature gauge to monitor how hot it is getting. That way your not taking any chances.

Next up is the solenoid for the front axle disconnect. When this goes bad your stuck with 2wd and its usually right when you need 4wd the most. My brother (when he had his 91) carried a spare in the glove box as it failed him several times. These are also a good investment: http://www.4x4posi-lok.com/app_chevy-k.html as they eliminate the solenoid altogether.

Again great pickup can't wait to see more :coffeedrink:
 

96discoXD

Adventurer
Thanks Rot Box, I'm wondering about the 700R4 too, but so far on the highway it's been really good, it hasn't been in and out of gear at all cruising along at 70-75. I do have a trans cooler in the stash that I may add later, but I can get a 700R4 rebuilt really cheap, so I may just pick up a core and have it done then do the cooler with a new trans.
I'll have to look into the solenoid. My '90 has a lever operated transfer case, no push button stuff, so I don't know if it still has the solenoid or not. Defintely worth checking into though, like you said there is nothing worse than not having 4wd when you need it.
As for the idler arms et al, it does have a little play in the steering so that's on my list of items to inspect and repair as needed. I will only be using all new Moog parts, no chinese auto parts junk.
 

Rot Box

Explorer
My '90 has a lever operated transfer case, no push button stuff, so I don't know if it still has the solenoid or not. Defintely worth checking into though, like you said there is nothing worse than not having 4wd when you need it.

It will still have the solenoid. The lever shifts the transfer case in and out of gear and the solenoid activates the front right axle disconnect at the same time. One great feature with the Posi Loc is you gain the ability to run Lo Range 2wd. Its nice to go slow and putt around and not have to bind up the drivetrain while having the front end engaged.

Call me crazy but I saw a noticeable increase in horse power by switching to a 185* thermostat on my old TBI motor. These trucks typically run well over 200* while cruising and the lower temp t-stat made a difference for me. That said an even colder (for lack of a better word) thermostat--like 165*--will trigger the cold idle and cause the engine to run like the choke is on all the time :snorkel:
 

96discoXD

Adventurer
Thanks for the additional information on the solenoid. I'll do some research on that. I have to replace a u-joint on the front driveshaft, perhaps that will be a good time to address the solenoid too.
As for the temp, this one has a cooling system that is in great shape and a lower temp thermostat already. It cruises down the interstate at 70-75mph without ever getting over 180-190.
 

96discoXD

Adventurer
Well, I got the rack mounted on the roof today (although it was just sitting on the roof in the attached pics). I ended up using the stock Yakima hardware and just drilling holes in the skin. I used the DCU aluminum crossbars inside as you would use crossbars on a roof rack. It's very sturdy and should easily hold the total of 165 lbs that would be the max load up there including the weight of the rack. I also fabbed up some ugly, but functional mounts for the shovel/axe on one side, and the hi-lift on the other.
I fabbed up a crossbar for the rack from 1" emt conduit to test-fit the lights. I'll probably do something a bit more permanent and better looking ultimately.
I also started insulating the topper. I'm using a 1" foil-backed from from Johns Manville, which I purchased at my local home improvement store. I think two 4x8 sheets will be enough to do the entire interior. It's a little on the tedious side cutting all the little pieces, but it's coming along. I will glue where I need to but otherwise probably won't I will cover all the seams with a yet-do-be determined tape and then I'm going to glue in a nice charcoal indoor/outdoor carpet over the entire topper interior except where I need to leave clearance for windows/latches etcetera. Here are some pics of the progress.
 

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