1993 K3500 1 Ton Dump Truck Build

[DieselAmateur]

Starting a build thread as this project is hopefully nearing completion, it's been a project since acquiring the truck in 2021. Have some specific questions including modifying/ upgrading the A/C system to R134 and adding a compressor with a pressure switch and adding a cluster with a tach, grateful there's a community here to help with such details.

Anywho I bought the truck in the fall of 2021. I was tired of paying to rent dumpsters for my construction jobs or paying a neighbor with a similar K3500 to haul away junk. Having another tow vehicle was another plus although as fate would have it my K2500 would get parallel parked a year later and remains sidelined to this day although it is next in line once this project wraps up

I briefly contemplated buying a duramax one ton, there was a LBZ truck in decent condition available for around 10k. But I ultimately wanted to stick with the platform I know and avoid a fully electronic engine and transmission.

I wanted 4x4, and a manual transmission. After several trucks fell through I found the truck that checked all the boxes, except the running part. The truck was being sold with a smoked 6.5, but it had all the desired features, including already being a DB2 engine. The cherry on top was the truck has a PTO driven hydraulic pump, no electric over hydraulic tomfoolery to mess with. The truck was owned by a tree service several hours south of me and was not driven in winter. Despite some rust, for the northeast the frame is mint. Worst rust is the fenders, they're so rusted that there's no good metal for patch panels to adhere to, the fender flares are keeping everything together at this point



Here's a video of the blown up engine, hole blown in the oil cap, head gasket gone as it wouldn't hold coolant and I'm pretty sure that's steam coming out the tailpipe

 

[dbrannon79]

compared to my 93, that is not much blow by! it also sound good for a blown head gasket.

Rig looks good too.

 

[DieselAmateur]

I had been keeping my eye out for an engine as I knew any stock truck would be a time bomb and I need the truck to be reliable for work. For once I would have good luck as I found an optimizer takeout ~5 hours away in Cleveland. The original owner of the takeout had installed new optimizer heads (must have been a centermount engine) and head studs but didn't seal them properly so they leaked. He gave up on the leaking studs after only a few hundred miles and sold the engine to the fellow I purchased it from. He had plans of fully restoring a crew cab truck and using the engine, but he was now moving south. So I scored an optimizer block with like new heads and head studs for $1200 in 2021, steal.

So with some money saved it was time to invest in the engine. Forged crank and P400 heads, block shipped to Chris for the full array of piston and head coatings, gapless rings, 18:1 pistons, splayed mains, girdle, valve springs, pushrods, mild port job, and timing gears







Engine getting crate built to ship, had to protect the decks with some good old fashioned lumber

 

[DieselAmateur]

Not much happened in 2022 aside from the engine being shipped out. I was part of a wild project building two new silos into homes with an hour commute so that ate up most of my time. Additionally my mini excavator was broken down for almost half the year and that repair sucked up whatever remaining funds I had after my commuter car had both injection pump and turbo failures. Throw in the K2500 with the P400 getting sidelined in the fall with IP issues and then a rod knock and 2022 was not a good year for diesels owned by yours truly









The curved stairs were both fun and tricky to build

 

[DieselAmateur]

2023 saw some progress, GMT800 front brake upgrade and a custom front crossover for the Banks sidewinder manifold. I had purchased the manifold in 2020 as something of a panic buy when covid hit, and was glad I did as it's no longer available and a better configuration than stock.

I did a separate thread on just the sidewinder manifold upgrade, link below

D

Thread 'Banks 6.2 Sidewinder Manifold Upgrade'

Oct 26, 2023

After sitting on my shelf for 2 years, I finally got around to making this upgrade happen. Sadly the Sidewinder manifold is discontinued and no longer available from Banks, but hopefully this helps the few who already have one or are lucky enough to score a used one.

There are several others who did this upgrade years ago so credit goes to those who paved the way. I hope this can help folks in the future too.

Parts needed:

Banks Sidewinder Manifold, #51002-00
Van/ Hummer exhaust manifold, RH #10238373
GM EVO delete tube, GM #19168825
Power steering pressure hose from 97+, I used GATES...

• DieselAmateur
• Replies: 15
• Forum: 6.5 Performance

• 

I also picked up a dually rear end from a GMT800 cab and chassis truck, as the rear end was cheaper than a rear disc conversion kit. The guy selling the rear end claims that the spring perches on the Cab & Chassis rear end of the 800 series are the same width as the GMT400, meaning it should be a drop in replacement. I haven't measured to verify this, but ultimately it's not a big deal to weld on new perches if necessary. Best part of meeting the guy selling the dually rear end was he had a set of the unicorn knuckles that don't require reaming of the tie rods, and he was kind enough to ream the upper ball joint for me. I chose to install new GMT800 LCAs instead of used forged lowers. I also purchased NAPA/ Mevotech inner and outer tie rods, and found that cotter pin hole for the inner tie rod stud is not deep enough on the threads. I tried alerting NAPA to this issue and they didn't believe me or seem to care about a production defect, so just be ready to use washers if "upgrading" to the TTX line of inner tie rods. I got tie rod sleeves from Cunningham Machine which appear to be a nice beefy upgrade

The GMT800 dual piston front caliper vs GMT400


Getting rid of the stamped lowers involved a lot of time with a cut off wheel and a chisel. Good riddance




GMT800 LCA with anti-seize on the torsion bar, much better




Inner tie rod showing the manufacturing error of the cotter pin hole






Needed several washers to seat the upper ball joint properly in the GMT800 knuckle



And one washer for the outer tie rod to seat

 

[DieselAmateur]

I've only seen one video where the GMT800 lower was used in this conversion, and there were no clearance issues with the shock/ no modifications needed to the 800 LCA shock mount. However on this truck the shock rubs against the edge of the bump stop mount on the frame. The front end has been jacked up this entire time so I'm hoping that the outward spread of the front suspension with weight on it will pivot the shock away from the frame. I recognize that the shocks being used may also be a wider diameter than stock. Worst case scenario I guess I'll have to elongate the mounting holes of the lower shock mount and slide it outwards. From looking at the photos it doesn't look like there's much meat on the mount for modification so I may have to make a new mount entirely








As the background of this build shows the truck is outside in the grass. No covered let alone heated space is the main reason this has taken so long to chip away at. As such I'm now coining the phrase "Mud Puddle Mechanic" as the traditional shade tree mechanic moniker implies the presence of shade, which is something I don't have! Mud on the other hand...

 

[DieselAmateur]

As I'm sure many a 6.5 owner knows, a benefit of a smoky leaky engine means an oiled and preserved frame. At first I was just going to pressure wash the frame/ engine bay from the cab forward and undercoat with Fluid Film. Seeing how nice the frame was though and not being entirely too jazzed about working around a wet undercoated frame I wire wheeled, primed and painted everything the best I could. I just used oil based enamel tractor implement paint from Tractor supply. One of these days I hope to give all my frames the full KBS rust seal replacement but until then this will be better than the rattle can job I did on the 2500 some years back

She was dirty



But cleaned up nicely

 

[DieselAmateur]

Since this was an early 90s engine, the bellhousing to engine studs were SAE. I couldn't find the exact GM part number for the metric studs, but found something close that needed to be shortened only a little bit. GM Part # 11546890



Needed to remove only ~ 1/4" to match the old studs




I also took the time to cut and flare the supply side fitting of the FSU. I've always hated the GM/ Saginaw fittings used on this fuel system. I also found out the hard way that the FSU for a Cab & Chassis truck is different than a pickup. The metal was also somewhat difficult to flare, it was really hard and needed some heat to form properly. I haven't tested it yet, fingers crossed






I also found a cast iron bellhousing that wasn't cheap but couldn't pass up the opportunity to put a stronger component between the engine and transmission.