The Stovebolt Site Forums The Shop Area Engine Shop bull low 4 speed how common?

i didn't think the granny low(bull low 1st gear)4speeds were that common in55,56,57 chev trucks. but 3 out of 4 trucks i have seen lately at shows had them instead of 3 on the tree.so my question is was the 4 speed real common ? my truck is 4speed as well. just curious. :rolleyes:
george

They're not rare, by any means. I think all the 3/4 tons of that vintage had the granny box, most of the 1/2 tons had the 3 speed. Designation for the tranny is SM420.

OK, next question- - - -what's one worth? I saw one of these at a local wrecking yard, supposedly in good condition with a V-8 bellhousing attached (the one with the crossmember motor mounts) and the asking price was $100.00. I don't need it, since I've got the same setup in my 59 Suburban, and about 5 of the hydraulic-clutch V8 bellhousings, but the price seemed to be good.
Jerry

Jerry, I've seen them sell anywhere from $50-200. The 4x4 guys love them with the 7.00 granny gear. They fit into a jeep without a lot of work. The SM465 with its 6.55 first is desirable and more bulletproof, but considerably bigger and heavier. If I needed one, I would pay $100, but not just to have it sitting around. Of course, in some areas they are as scarce as hen's teeth, but not here.

I've got a couple of them already, one original-equipment box in a 59 model 3800 1-ton, and one of uncertain year that I swapped into the Burb about 20 years ago. I think it's a late-60's trans. Do you think either of these would handle the torque of a 120-HP turbo diesel inline 6? I'm considering building up a 3/4 ton running gear with that engine, a takeout from a UPS box van. Not sure which cab I'll use, as I've got a couple to pick from. It's probably going to get a home-built wrecker bed installed on it.
Jerry

My 1963 Chevy Shop Manual lists the input torque capacity of the SM420 as 281 ft-lb. It was used, however, in 50 and 60 series trucks with all available engines including the 348 and 409 V-8.

What's so scarce about hens teeth anyway ?

I have an extra one in my garage which came very handy when I decided to install a backup light switch in my tranny. Used the top plate of the spare tranny as my guinny pig and it worked perfectly. Swapped top plates and everyone is back in their places, fat and happy.

I have 3 of them and have turned down a couple more free ones, one of which had the PTO attachment. They are pretty common around here. I wished I had taken the PTO tranny, because the 51 3/4 ton wrecker chassis I bought has a Galion winch, but somebody borrowed the PTO from it.
Ralph

Hello Hotrod, I thought that all UPS trucks went to the great parking lot in the sky. how did you come across an engine from UPS? At one time there was a thread about the 18 or 19in wheels that were on the smaller box vans with 8 lug holes that supposely fit on the front ends of the 3/4
and one ton ads without fouling the tie rod ends. Do you know anything about this?

tony'n weatherford

I'm curious about the wrecker bed. Have you already built it, or are you just planning to build one? Have you made plans? This is something I've thought about doing...

Scarce? Oh yeah. Here in Hawaii there are way more 4x4 builders than old stovebolters so open driveline SM420s are nearly impossible to come by. Shipping one in from the mainland costs an arm and a leg, too.

these tranny are in a lot more old trucks then i originally thought! abuddy of mine even has one swapped in a jeep.

I made a one-time racehorse deal on 8 retired UPS engines, with a buddy who was a shop foreman for UPS. I got 7 running engines, and one without a cylinder head. (I paid just about scrap iron price for running engines!) They're 120 HP turbo diesels, about the size of a 292 Chevy, but somewhat heavier. I dynoed one, and it makes its rated horsepower, 120 @ 3600 RPM. I've got 5 running engines left, and the parts engine. They were made by Onan as power generator engines, and when Cummins bought Onan, they sold them to UPS as delivery van engines. The UPS demand exceeded Cummins' ability to supply spares, so they retro-fitted to a different engine. These engines were used interchangeably with 292's and F*rd 300's, so a van could be converted from gas to Diesel with just a fuel change. They're set up for Chevy V8/292 bellhousings, with the old hydraulic-clutch bellhousing with the throwout fork on the passenger's side. They're equipped with a 12" Chevy clutch, and any Chevy-pattern trans will bolt up. I've got a New Process 235 4-speed to use on this project, but I'm searching for a 5-speed Clark with 5th. gear overdrive, with a Chevy bellhousing bolt pattern. No luck on the wheels, as my contact man retired a couple of years ago!

I've got a line on a couple of wrecker beds, with PTO-driven winches, or I might fabricate my own bed and booms, and use a PTO winch. I ran a wrecker service for a while, and did most of my own maintenence, and even built a few special-purpose beds and rigging. This project is way down the "to-do" list, so I'm not locked into a final design yet.
Jerry