Project: Tow-Rat (Lil' Blue)

[6DoF]

Originally Posted by slammed57

Really cool build you got goin

Originally Posted by big_dan

Definitely going all out. Love it.

Following for sure.

Dan

thanks! i wasn't sure if anyone was even looking at my thread there for a while ... but i'll keep updates going.

[6DoF]

been doing a lot of prep work on all kinds of parts from the trans crossmember to the fuel tank mounts. re-designed the mounting of the crossmember though. this new design doesn't require drilling into the frame, will hold weight with no nuts on the bolts still, and can be removed down or back with no binding. no it's not double shear, but the loading doesn't require it at all, and not having to slot the bushings will make everything easier.

i've also been doing a fait bit of welding on the frame, and even got the rear brakes set up. 2008 GMC 3500 rear rotors, standard 14B studs, GM 3/4 ton D52 calipers, and BTF weld on brackets that have been in my shelf for like 10 years. the studs are a tiny bit sloppy to the rotor holes, so i wrapped a little tap on 2 studs to center them before pinning them in place with all 8 studs. nothing should move, Pirate4x4 couldn't even argue it works great, but another one of those "i guess we'll find out". i didn't feel like having custom sleeves machined if i didn't need to. had shims between the rotor and the caliper, more shims caliper to bracket, new pads, then made an adapter to hook the caliper to my air compressor. held everything square n tight while i tacked em in. yes the bleeders will be on the right side when actually installed, and they are installed below the axle to make sure they don't have any chance to hit the frame on articulation. looks weird to me though since i'm normally trying to keep them high from hitting rocks. lots of wheel clearance, so game on.

[6DoF]

Got the rear links as far as I can until I get my cnc cut plate to keep going with bag mounts and the link mounts themselves. I even managed to not warp the thread insert!!! For reference I used a 1-1/4" threaded bushing.

[6DoF]

i'm torn on steering and brakes currently

Steering:
rack and pinion vs stock style C30. cost, function, effort to install ... i feel like everything really leans towards the stock style, but then why is a rack n pinion so sought after?

Brakes:
has to be hydroboost for the diesel, but under the floor vs firewall mounting. i can't find any real comparison on this. i'm leaing towards this, thoughts?

https://www.performanceonline.com/HY...irewall-Mount/

[Rickysnickers]

Nice work. Those are some serious trailing arms!!!

[6DoF]

Originally Posted by Rickysnickers

Nice work. Those are some serious trailing arms!!!

when i get the urge to build this 12V too far ... i don't want to loose the rear axle passing a Prius going up a grade towing a 10,000lb trailer

[6DoF]

officially decided to go stock C30 steering. started getting mounting locations into 3D so i could figure out how i wanted the frame up there to look ... and it looks like the drivers side core support body mount is located inside the steering box

i can build a new mount on the core support, not a huge issue ... just means if i ever get new sheet metal i have to re-modify it. oh well.

[6DoF]

first up was another mod to the LCAs for steering. the extreme back spacing coupled with the extended travel got the wheels into the outer lip of the CA that's turned up. so i went about adding some gussets inside and under the arm before cutting back that clearance. i chopped the lip back about 3".

at this point the LCAs should only need a bump stop added to be all set. i am also however having a clearance issue with the UCA and the Belltech brake caliper mount gusset on the knuckle. currently that's my next steering stop. and should be the last clearance issue to get the full range of steering out of this box/geometry. full range is just better than 35deg i think, and that's not bad. the sheet metal will still be a limit depending on height though, stay tuned with me to find out how much. haha

then got everything back together to re-test just as my steering box showed up finally. so the steering is all on there and making sure i got it in the right spot.

[6DoF]

ok, i know one of ya'll has a set of these sitting around somewhere. is anyone willing to part with a set of solid, but properly patina'd pair of tow mirrors like these?!?!?




i guess worst case i can still get new ones for pretty cheap

https://www.summitracing.com/parts/ksc-h3641#

[6DoF]

i got a 2002 Yukon 2nd row seat, $60, and is actually a white-tan that goes reasonably well with the truck. I'm happy enough for now to not bother with covering it, so that's a win. the seat is also 1/2" shy of the door on each, and tucks perfectly into the rear cab corners, it's literally MADE for this truck!! though, you'll notice i cut the head rest posts off. they still need some love eventually.

mounting brackets on the other hand will be the trick. i've convinced myself that the tubes under the seat are only there for a GM factory assembly aid, and serve no structural purpose once bolted to the floor. will require that i take the time to align everything well, and the auto-release seat back latch won't work because the cable mount will go away, but that's fine. fwd hinge bracket will get bolted to the floor directly in front of the rib, while the back will get bolted directly to the rear rib that is under the boards. same angle mounting as pictured, just lower.

passenger seat obviously folds just like the drivers side for great access for putting tools n junk back there. maybe even a weekend duffle bag so it's not in the bed on a trip. the tubes going away also really open up under the seat storage.

[GreasyLikeaBurger]

that does fit pretty well. Lots of potential to customize it how you like it.

[dsraven]

looks like the seats were made for the cab.
will you have a park brake? is it a requirement where you live? it would be a shame to build with no park brake and then have to modify to pass an inspection. will the "stop" be enough for the amount of "go" you have in the build?

[6DoF]

BOOM! Time to play

[6DoF]

Originally Posted by dsraven

looks like the seats were made for the cab.
will you have a park brake? is it a requirement where you live? it would be a shame to build with no park brake and then have to modify to pass an inspection. will the "stop" be enough for the amount of "go" you have in the build?

Im excited about the seat, seams better than expected so far. Should be great on a long trip too.

PA does have inspections, but im pretty sure I'll register antique and be exempt from both safety and emissions inspections. If i do register normal to 'legally' tow, a "parking brake" is required but not an "e-brake". Defined that it must hold the vehicle from rolling down a slope while in Neutral. Nothing about an "emergency" or mechanical back-up brake. For parking i use a Parker ball valve, you push the pedal hard, shut it off, and it holds full PSI on the calipers. Started that in my rock crawler for winching, but they keep full hold for months+. Also no way for a cable or springs to seize/brake. There is a risk someone bumps them off while driving, but not 2 or 3 of them.

The other option however is the cadi d52 caliper that fits these brackets. Recently RuffStuff started making them all new cuz they got too hard to find. Now, they are not exactly the same as the standard gm front caliper though, its a slightly smaller piston. This does however help with brake proportioning.



https://www.ruffstuffspecialties.com...YaAquIEALw_wcB

Total piston area:
Stock D52 ----- 6.78
Big dual piston d52 wilwood -- 6.28
Small dual piston d52 wilwood -- 2.46
Cadillac ('76 -'78) Eldorado E-brake Calipers -- 4.55
79-85 K20 JB7 front calipers -- 7.82 (metric banjo)
GM 1-ton caliper -- 8.90

So for stopping power. Im running the stock 1-ton front and a stock 3/4 ton front d52 on the rear with hydroboost. Im pretty sure that will be great with only a 30" tire. The 1-ton piston area is very similar to modern factory dual piston on trucks. My only concern right now is that i went hot-rod on a fancy looking wilwood master cyl, but its only a 1.125" bore. This was the max i found in a bling master. These calipers could use a 1.5, or even 1-5/8" bore master. Ill get better PSI from this smaller one, but I'll have a long pedal travel to do it. I have a Jeep running the same set up on 40s, stops great but takes a lot of travel. We'll see, might end up with a large bore stock application master.

[6DoF]

Just cuz, he's my Jeep for reference. Was my first car n still have it! Used to compete rock crawling, mostly just for fun now. I plan to tow this with the 55 to the trail.

1991, 4.0 I6 bored n stroked to a 4.6, 5spd. Gm kingpin d60 front, custom full float "1-ton" Spider-9 out back. 5.38 gears, dual air lockers, 40" Nitto's, etc.

[dsraven]

I think your tonka truck is making a break for it. haha

[6DoF]

started knocking out fitting the plate on. ended up spending 1.5h trying to find what was off when i measured the wheelbase and it was off. turns out the frame and crossmember and true n square (<1/8" over the whole thing), i better placed the rear axle, and the front suspension that i never did an alignment on ... needs an alignment

tonight i hope to get the WATTs link in place, and maybe even the first set of bag mounts. once it can support it's own weight, then i'll drop on the body mounts. I'm pretty sure i want to get all the fish plates at least hard tacked in place before i drop the body on too. but my goal is still to have the body n front clip on the rolling chassis before the end of the Jan.

[6DoF]

Originally Posted by dsraven

I think your tonka truck is making a break for it. haha

she won't get far, it's anything but fast or fuel efficient

[6DoF]

got the Watt's back in place, feels good to have the rear axle fully constrained again.
started to assemble the bag mounts, and did a test fit of the fish plates. for a size comparison, i do NOT have small hands

[6DoF]

Boom, roller

[Rickysnickers]

Wow, nice!!!

[dsraven]

Lookin good. Gotta love it when the wheels go on.
Will you fab a link, cut to length or adjustable, to replace the air bag during the fab part of the build? Keep ride height the same and no burn holes in the rubber from flying weld spatter or grinding sparks?

[layinrocker65]

I like where this is going. Keep up the good work

[6DoF]

thanks ya'll!

Originally Posted by dsraven

Lookin good. Gotta love it when the wheels go on.
Will you fab a link, cut to length or adjustable, to replace the air bag during the fab part of the build? Keep ride height the same and no burn holes in the rubber from flying weld spatter or grinding sparks?

currently no plans for a bag-simulate, but if i do it'll just be a 2x4 between the axle and frame. nothing fancy for that. when i was burning in more of the steering up front, i used an amazon box as a shield. didn't even catch fire! most of the time i'll probably just have the bags out on the shelf with the frame up on jack stands.

[6DoF]

and after a minor adjustment last night to the watt's brace that i put in the wrong spot, she'll lay out. full drop, full lock-to-lock steering is still good. lots of frame clearance, but touch the steering box by THAT much ride height has 1/2" clearance, and the sheet metal won't let me steer that far at drop anyways.

i'm also reasonably impressed by the steering angle i'm getting out of the stock parts. this 35deg+ will be 1000x better than the old Ram chassis.