The Stovebolt Site Forums The Parking Lot Tons 'o Fun My 1 ton project

Well here goes, I had a nice 50 3800 ex firetruck with low miles and completely solid and straight body. It was powered by a dual carb 261, it ran and drove really well. I was going to upgrade to a 302 gmc so I pulled the engine and completely stripped the cab in preparation for a full paint job. Meantime I find another project or too ( I got AD ADHD, anyone relate? ) and get an offer on the body I couldn’t refuse. Well I miss having a 1 ton and I’ve got a 48 gmc 1/2 ton longbed which will make a great cruising truck so I traded my chassis back from a buddy and I’m going to put together another 1 ton for a DD. Currently have a 261 in the machine shop. It’s gett an edmunds 2x2 intake with Langdon Carter Weber setup, bulldog cam, small cap HEI, Fentons and full balance of reciprocating assembly. I just picked up a Dana 61 axle from an early 90s Dodge and a New Process NP540 direct drive 5 speed trans. The rear ratio is 3.07, with 7.41 1st gear and 4.05 2cnd in the trans I’ll be able to pull/haul anything I want to and drive the interstate too.

I’m not seeing the caption with my pics. The yellow and black truck is a 47 3/4 ton I’ll be using it’s cab. The primer and red truck is my old 50 3800 ton I’m using it’s chassis but going with single wheels for practicality/economy’s sake. 16x6 F250 wheels, common 235/85R16 tires. The last 2 pic are of course the NP540 5 speed.

Looks like a good project!

I like your tranny stand!

Don't forget, GMC's are about 3" longer than Chevies.

NP 540 series make great trans' for your application, I have adapted several to 4wd applications.

Ed

Ha! It’s a little rickety I used 1-1/2x1-1/2x3/16 angle cuz I got a bunch of it, 2x2x1/4 woulda been better but it’ll suffice. Thing weighs 175 lbs I didn’t feel like wrasling it in the floor or on the work bench so I spent most of a day making it. I can sit in an old swivel office chair and play with it, definitely worth the time!

I’m decided to save the 302 for my 48 gmc 1/2. I’m getting 261 and 848 head machined right now for it, will have Edmunds 2x2 intake with Langdons carter Weber setup and some other goodies.I’ll have to swap a stock Chevy crossmember back in the frame because I modified the original to fit the gmc. These pics show what I did to the crossmember, I couldn’t resist adding one of my 302 I made the intake outa steel, it’s too heavy but hey it ain’t a race car. As much as I love the old SM420 4 speed im sure this 540 trans is going to be so much better. With the 3.07 rear gears I’ll be able to downshift to 4th and still maintain 55-60 mph

Thanks, I know I’ll really enjoy driving it and using it like a truck I hope you guys will check on me from time to time and help me stay motivated I’d like to get this thing running in the next 6 months to a year.

I put a 540 in an early Bronco with a Buick V-6 and 3.50 gears; with a load, shifted around 55 to 60, worked very well.

Ed

Just what I’m hoping for.

This is an eBay find. Got it for 150 bucks but had to drive from here in perry county Arkansas to Ponca city Oklahoma and back yesterday to get it. It’s a Dana 61, just like a 60 but with 3.07 or 3.38 ratio, this one is 3.07. They had to use a really large pinion gear to get that low number ratio so it’s located farther over in the housing than it would be in 60. They were used in Dodge and fords when they first came out with diesels in the late 80s early 90s. Neither make had overdrive transmissions yet making these ratios necessary so as not to over rev the engine. This is 65” from WMS to WMS. Darn near perfect to replace an original that was 62-5/8, it would even work on a pickup with original fenders. Original or the later Chevy stepvan 19.5 dual wheels will clear the brake drums. I’m thinking this particular axle came from a ford, my Chevy wheels won’t go over the hub but ford wheels will. It won’t be a big deal to get the wheel center hole turned out to fit it. If anyone knows of a way I can figure out exactly what it came from please let me know as I now have two 1 tons and this looks to be a cheap easy way to make one drivable on the interstate and it would make it easier to find another one.

Thanks Robert -- THAT sounds like really useful info to to tuck away ... Especially the other 3800 DRW guys. Sure would be nice to have some sort of an article come out of this to be a companion piece to the rear axle article we wrote on the 3804 (SRW) HO72 axle....

John when I find out more info like exactly what truck this came out of I’d be happy to write up a small piece with a few pics for the tech section. I was thinking this axle was from ford but since learning that there’s only 1/8” difference in hub size, dodge = 4-3/4, ford = 4-7/8. Getting a machine shop to enlarge the hub hole on dual type wheels is no big deal and 3/4 ton ford wheels work really well in our trucks and hubcap lips can be added to them as well. If a guy doesn’t like the idea of using a ford or dodge under he should remember Dana axles were used on GM trucks too. Most all trucks with leaf springs from 60-72 had Dana axles. Great things about Dana axles, they are so universal that parts are readily available and quite common. The ratio choice is good too, even with the much more common Dana 60 3.55 and 3.73 is readily available. The 3.07 is perfect for me with my direct drive 5 speed trans. With its 4th gear raio I can down shift if I need to and it will be just like running 4.50 rear ratio 1:1. I can still maintain 55-60 with that. If I down shift an SM420 4 speed I’ll be doing 30.