1994 K3500 extended cab dually

[n8in8or]

Nice work! the only thing I would be worried about for the future is the flex joints. when the day comes they start leaking and you need to replace. iirc they make them with v band flanges so that they could easily be replaced, wonder if you have clearance for that though.

Though on my 95 I just about had no choice to cut my down pipe and splice in a 4" steel flex pipe to alleviate the stress and from it banging the frame to the 4" exhaust kit I installed. It's been on there for a while now, all rusted but still holding up LOL. your stainless should last for years to come!

As long as I make my cuts straight, it won’t be bad to replace them in the future if the need ever comes.

 

[n8in8or]

It took 2 days, but I finally have the post-turbo exhaust done (mostly).

I installed an FTE Diesel muffler/resonator on it again because the sound was great and I had zero drone in the cab. It’s 409 stainless.



All tubing is 304 stainless. I started TIG welding all the joints. Oof. That took so long and I wasn’t happy with the results - not only did my beads look like crap, but I’m also not set up to backfill the tubes with argon, so I wasn’t getting great corrosion resistance anyway…..so I ended up welding all the joints with carbon steel MIG and was much happier with the results. The downpipe starts 3” and transitions to 4” before the flex joint. I left the end of the exhaust unfinished so I can make the tip align with the bed how I want and not have to rework it after the bed is installed…..I learned that lesson on the red truck.

 

[n8in8or]

Remote oil filters are installed. I used a Canton remote oil filter adapter and Fragola -10 AN lines and fittings. I bought the oil filter mount a while ago and can’t remember the brand.

 

[n8in8or]

This evening I loaded the chassis up and took it to a local cruise-in, just for funsies. Also had to pop the hood on the Tahoe.

 

[MrMarty51]

This evening I loaded the chassis up and took it to a local cruise-in, just for funsies. Also had to pop the hood on the Tahoe.

View attachment 95886View attachment 95887View attachment 95888

I’d think that would have got quite a bit of attention from the true enthusiasts.

 

[n8in8or]

I sandblasted the manifolds and hit all the welds on the rest of the pipes with a stainless wire wheel. After that I painted the manifolds, crossover pipe, down pipe and resonator/muffler with KBS Xtreme Temperature Coating. And finally I wrapped the crossover and downpipe with DEI header wrap. I installed the manifolds with Stage 8 header bolts so they won’t loosen up. I also wrapped the starter with some heatshield material I had in stock already. It’s ready for the cab to be installed now.

 

[dbrannon79]

Nice!!

question, how low does that crossover hang (from the ground) I assume you are planning for suspension lift or tall tires for offroad shenanigans.

 

[Twisted Steel Performance]

Ya gonna wrap the manifolds ? That would really keep heat out of the engine bay...

 

[n8in8or]

Nice!!

question, how low does that crossover hang (from the ground) I assume you are planning for suspension lift or tall tires for offroad shenanigans.

The crossover isn’t any lower than the diff skid plate so it’s ok. The pics are deceiving.

 

[n8in8or]

Ya gonna wrap the manifolds ? That would really keep heat out of the engine bay...

I’d like to wrap them, but the old manifold was rusting under the wrap so I didn’t want to promote that happening again.

 

[dbrannon79]

you can always keep the ones you just made as spares/mockup units and re-make them with any added design changes from stainless, then wrap those LOL

 

[n8in8or]

I’d really like to have the hot side coated in this stuff, but it isn’t cheap so I’d need to make sure my design all works how I want before I make that investment. If I am happy with it, I could blast the stuff and send it to them or make a new setup and send it to them for coating. This way I have heat containment without wrap that will trap moisture between it and the tubing. I was turned on to this stuff when I was working on building up the 460 in the Class C motor home we had - it’s supposed to do a great job of taming heat when applied to headers in that application.

White Lightning Exhaust Coatings – Swain Tech Coatings | Industrial Coatings | High Performance Racing Coatings

 

[n8in8or]

Got the cab on today. Took longer than I anticipated, but the task is done.



Unfortunately I found that the downpipe hits the cab - even when it’s detached from the turbo. I thought I was going to have tons of room with where I put it and have the best heater hose situation I’ve ever had, but I guess I screwed up, so downpipe mods upcoming.

 

[dbrannon79]

Nice work! wonder if you were to custom make a sharp 90 with flanges on both sides, then tweak the down pipe if that would give you some extra clearance.


something I have always wondered... on these gmt400's what it would take to convert to a short bed. I keep picturing in my head of my 93 CC LB getting a short bed.

 

[n8in8or]

Nice work! wonder if you were to custom make a sharp 90 with flanges on both sides, then tweak the down pipe if that would give you some extra clearance.


something I have always wondered... on these gmt400's what it would take to convert to a short bed. I keep picturing in my head of my 93 CC LB getting a short bed.

I’m going to mockup the core support and inner fender, plus put the AC line in place so I can truly see what my envelope is and then optimize the downpipe to fit. I’m still shocked how tight it is. I think the way I did the #8 tube ate into my space more than I understood.