The Stovebolt Site Forums The Shop Area Engine Shop C-30 with a T-5?

I have a 1962 C-30,and am wondering if a T-5 could work in it. I've seen lots written about installation into half tons,but have found nothing regarding a one ton swap. My big concern is the strength with the one ton's towing capacity,and overall vehicle weight. It's kind of a general work truck,so I need it to be able to do a lot of different things reasonably well. So far,it does great,except in highway driving. Out here,towns are 100 miles or more apart and in this truck,it takes all day to get anywhere,and the mileage isn't too great either.
I'm convinced an overdrive high gear would be a great help in both of these areas. I would install a crossmember at the tailshaft,to strengthen the drivetrain as much as possible,if this idea can be made to work suitably. If the T-5 isn't a good move,what else would be a good choice?
I thought about going for a taller geared axle,but some of the jobs I get involved with require traversing fairly rough ground at a pretty low speed,and I don't want to run a much taller first gear than I have if I can avoid it.
Speed

Hey Speed;
Probably the best solution would be an aftermarket overdrive, like the Gear Vendor's, but these can be pretty pricey. Don't just grab any T5, they came in all kinds of configurations, the first thing you would want is a WC (World Class) box. Stay away from NWC. The WC was built for V8 Camaros and Mustangs and is pretty stout. Also has better bearings and Synchros. Try www.5speeds.com/t5 for all kinds of info. Good luck!

With a little tinkering and some creative welding and machining, mount a Saginaw 3-speed behind the main trans, facing backwards. High gear will be direct drive, and when it's "downshifted" to second, you've got overdrive. Then all you'll need to do is fabricate an electric or vacuum shift system to shift from 2nd. to 3rd. gear. Leave the linkage off the 1st./reverse shifter, or lock it in the neutral position somehow!
Jerry

Speed,

Whats rear ratio are you running?

You will find that with most all transmission swaps you will have a faster first gear. Your 4 speed is about 7.14, or something close, in first gear. Only the NV4500 comes close to having as low a first gear and overdrive, at least for common transmissions that will fit. Although I don't think it is easy to swap to a 6 cylinder, very easy for a V8, call Advanced Adapters.
If you really need that low first gear then the gear vendors OD unit is probably the best answer.
An auxiliary transmission like a Spicer 5831 with the overdrive ratio is another solution, although it is a little bit heavy, needs two cross members of its own, and a good bit of fabrication to install it and the shift linkage. Unless you get lucky and find one still installed in a truck with all the goodies at a cheep price the Gear Vendors unit will be better bang for the buck. The Spicer unit will give you even lower gears, a direct, and an overdrive, assuming you find one that is not direct, low, and lower.

I'm running a 4.10 axle right now. I like the backwards 3 speed idea-I've wondered about doing that before. Seems like I remember my neighbor's Grandpa setting something like that up in his old Cornbinder tow truck years ago. He(and the truck)have long since passed on though,so I can't ask about it. Sure sounds possible,though. Once I have the Mack up and running,I can take some time on the '62 and get creative.
Going back to the backwards 3 speed idea-imagine if I hook up both shifting arms...
Speed

Don't get greedy on the OD ratio! I've seen the two transmissions on one of those Rube Goldberg rigs close-coupled by using two slip yokes and a single universal joint cross. Getting the input shaft coupled to the driveshaft takes some pretty creative maching, but it is doable for a determined tinkerer!
Jerry

I guess I'll have to slide under the truck and measure the distance between the tranny and the carrier bearing-that's the space I'd have to work with. I'm thinking some sort of bracket that bolts to the front(bellhousing) holes,goes down to a plate which goes under the 3 speed and connects to the lower 2 bolts on the tailshaft housing. This could be rubber mounted to a crossmember and bolted to the frame. For the input shaft(soon to become the output shaft),I think the bearing retainer could be cut back ,and a pillow block with a good heavy sealed bearing could be aligned and bolted to the facing of the bracket. The shaft could be cut to about 4 inches long and a u-joint yoke trued up on the stub and welded on. Not sure if it's possible,but I'd try to have a driveline shop have a go at balancing the welded up assembly.
The linkage would be on the right side,so probably a heavy cable control would be best. (Like a PTO cable the tow trucks use.)
I'll have to look around and see what second gear was on the ol' Saginaw 3 speeds. I'll bet I'd end up with about 25% overdrive.
Speed

Hey guys,
Been following this post with interest.
I have always wanted to try the backwards 3 speed overdrive idea.
Jerry, is there any reason why you particularly mentioned using a Saginaw? Any reason why a Muncie wouldn't work?
I have a Muncie 3 speed I was thinking of using with 1st and reverse gears removed, so it just has 2nd and 3rd. Photo

I think 2nd gear is 1.68, so flipped around backward, 1 divided by 1.68 = .595 overdrive ratio. Am I right here?

If this is correct...
4.11 rear x .595 = 2.45 final drive ratio.
4.57 rear x .595 = 2.72 " " "

Does this make sense?
I'm wondering if I do this with my stock '52 3/4 ton with 4.57 rear if my little 216 would be a little under powered for that OD ratio. Maybe it would be okay with the truck empty.

There's no particular reason for using a Saginaw, other than availability, (newer) and possibly a slightly more efficient 2-3 synchronizer on the Saginaw. If you've got a Muncie handy, I'm pretty sure it would work. I'd suggest making up a slip yoke for the "output" by using a couple of clutch disc hubs, machined down to fit inside a slip yoke with the splines bored out, then welded into place. By drilling a series of holes in the slip yoke, and "plug welding" the clutch splines in, you'll have a sliding fit, without destroying the input shaft on the 3-speed. The carrier bearing could act as your rear shaft support, so just rig a rear crossmember to support the bellhousing bolt pattern, and make another crossmember under the rear mount position on the 3-speed. For shifting, I'd use one of the vacuum-shift setups for 4 wheel drive transfer cases, with an electric solenoid or a manual vaccum valve for shifting. Spring-load the shifter in one direction, and use the vacuum chamber to shift it the other way.
Jerry