The Stovebolt Site Forums The Parking Lot Big Bolts 46 2Ton rear end

I just purchased a 46 2 Ton that I want to use as my shop truck. I am wanting to put a taller geared rear end so that I can drive at 60-65 with out any problems! I am very new to this site so excuse me if this has been discussed already. I am hoping to use the same wheels, drive shaft, brakes, etc.

Thanks, Randy

Hy RDomeck, welcome, if you can post the serial number we will know what size truck you have exactly. Is the rear end a single speed, or a two speed?

What is your rear ratio now? Is this truck running and driving now? If so what road speeds are you currently able to comfortably go?

Adding an auxiliary overdrive may also be a good option, although you would have to re-do your drive shaft and mount it.

The Serial number is

9PWG1549

I currently have a single speed rear end and I believe the ratio is somewhere in the 6.31:1 ratio! I have only drive the truck a very short distance, but I will be putting in the new gas tank that I made tomorrow and getting the rest of the fuel system in good order! To my understanding this truck is only good for about 45 MPH!

I really intend to use this truck so I would like for it to be geared higher. I run a fabrication business so I had already been considering an auxiliary overdrive put in line somewhere, but I thought swapping out the rear end would be the easiest!

Thanks for the help, Randy

I have the same issue with my 46 Ton with similar "PWG" serial number. I stack up traffic behind me on two lane roads and would love to be able to cruise at 60 MPH. But, they are geared low for a reason. The 93 hp engine is just not able to propel that much weight at high speed. If on level or down hill grades, you will be able to go faster with a new differential gear. But when you start up hills as we have where I am you will likely see your speed diminish quickly. The advice I get is that the taller gear may need to be coupled with a later, more powerful stovebolt engine. Anyway, I will be very interested in how your project turns out. Please post the results of your project and what you did to increase your speed so that I can learn from your experience.

you may be able to to add auxilary overdrive transmission. search for threads on brownlipe and spicer transmisions. Heard it rumoured Some fiftys era GMCs had 5 speed clark transmissions with overdrive. Not sure if they could be adapted if indeed they exist.

6.3:1? I wish I had that much gear to play with, I have 8.5/10:1 2 speed in my old beast!
However, with the 1:1 4th gear ratio, even at 8.5:1 I can run up to 60 if needed & it's pretty comfortable trundling along at 50-55. I would think that if your engine can push the RPMs you could run the same speeds. If not, adding more gear is just gonna make it into a pig that takes forever to get up to speed & cant climb hills without down shifting. Like Berry said, without an engine upgrade those gears wont be much help.
Oh, & dont forget your matching brake system upgrade! Going is optional, stopping is mandatory!

My owner's manual says your 46 diff is a 6.17 which is almost the same as the high end of the two speed diff which is 6.03. You could try to put 22" wheels on the back,that would help some. I don't know if it would be a good idea to go drive 60 MPH in a truck that was only designed for 45 MPH. My 46 didn't even come with shocks!

I would agree that going 60 in a truck that was designed for 45 wouldn't be a good idea! I plan on upgrading brakes and suspension. I'm looking into a dual circuit master with vacuum assist! I don't think it would be that hard to put shocks on it. I run a fabrication business and I would really like to use this as a shop truck. I'm thinking about a little bit more power in it, but haven't really decided. If I do I want it to have the same wheels and tires as it does now so most would think it's stock!

Thanks for all the help so far and I will keep you guys updated!

Research research research........ This site has a lot of answer's on it and I should have taken the time to read through all the tech tips and FAQ's.

I believe I will stay with this rear end for a while and see how it works out. I was able to adapt a single wire alternator by drilling two wholes in the original generator bracket. Everything lined up as it should, I can't believe how easy it was! I'll be finishing up making the wiring harness today. I don't think I will be able to drive it this weekend as I found a lot of sludge in the radiator and I want to have it cleaned before I get too far and overheat.

Thanks for all the input and you should see me in the gallery sometime soon!

This statement only really applies if you will be running the truck fully loaded at a higher speed. The truck was designed to stop fully loaded going 45-50mph. If you are running empty, or nearly empty for a 2ton anyway, at 60mph why do you think you would need to upgrade the brakes?

As to the dual master circuit....also I would say this is an unnecessary upgrade if your emergency brake is in good working order. Brakes rarely catastrophically fail, normally they will leak and slowly loose fluid over time. With proper maintenance the original system should be fine.

Just my 2 cents...but I believe way too many people modify old stuff because they feel they have to to be safe or reliable.