2 speed rear end possibilities

Sleddgracer

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south east BC, close to the Canadian/US border
I'm looking at a bus conversion that has a 2 speed rear end - I'm somewhat familiar with the split as I had a 56 Mercury 2 1/2 ton at one time that was equipped with the 2 speed rear end - my question today, would it be possible to replace the gears in the 2 speed so they become the faster highway gears?, or is it possible to replace the regular gears with something a bit more highway friendly than what the bus has now, and still retain the split gears for when more power is needed? - the bus has a rebuilt 454 with an RV cam, 4 speed transmission with the split rear end - 2800 RPM gets you 55 MPH on the highway - I'd like to hit 60 MPH with the engine turning about 2300 RPM :Thanx:
 
I'm looking at a bus conversion that has a 2 speed rear end - I'm somewhat familiar with the split as I had a 56 Mercury 2 1/2 ton at one time that was equipped with the 2 speed rear end - my question today, would it be possible to replace the gears in the 2 speed so they become the faster highway gears?, or is it possible to replace the regular gears with something a bit more highway friendly than what the bus has now, and still retain the split gears for when more power is needed? - the bus has a rebuilt 454 with an RV cam, 4 speed transmission with the split rear end - 2800 RPM gets you 55 MPH on the highway - I'd like to hit 60 MPH with the engine turning about 2300 RPM :Thanx:

....................any one?................
 
Basically yes you can change the ring and pinion, and leave the planatary gears alone. Or change the whole carrier in the rear. Any idea of what rear it is? Eaton, Dana, model number etc?

Mine is an electric shifted Eaton with 5.14 ratio in high. Was in the Vermont and New Hampshire mountains last weekend and made good use of the 2 speed. Steepest grade was 12%, so got to do some split shifting.
 
Yes, you can get the 2 speed axles in a multitude of ratios. What ratios are available depends on the axle being looked at. Most 2 speed axles that I've seen personally are around 5.xx/7.xx area, Which is too high for most people looking.

I have a dana/spicer catalog in front of me now, and they show their medium duty 2 speed drive axles are available with a 3.90/5.32 up to 7.17/9.77

You likely won't find any of those in a salvage yard though because 2 speed axles were coupled with old gas engines and all of that stuff is kind of a thing of the past.

So then you're looking at purchasing new parts, which is $$$$$
 
He is looking at an old gasser and mine is too.

So for me 60mph is at 2600rpm, and 70 is at 3000 with my rear and 10r22.5 tires which are 40" diameter
 
He is looking at an old gasser and mine is too.

So for me 60mph is at 2600rpm, and 70 is at 3000 with my rear and 10r22.5 tires which are 40" diameter

yeah, mine is an oldtimer - drive train has been rebuilt or gone over from one end of the bus to the other, rebuilt 454 with an RV cam, rebalanced drive shaft with new steady bearings, new brakes, new tires all the way around - all with less than 4000 miles on them - converted to a MH, but the conversion itself is rather shoddy, well worn and taken from an old MH or trailer, but everything is there and can be used this winter as is - $2600 US funds - tires and motor are worth more than the purchase price - my ticket is purchased and I'm flying north a week from tomorrow - he'll meet me at the airport, 15 minutes from his house, and if the bus is as it's supposed to be, he'll drive me 10 minutes in the opposite direction to the MV branch where I'll get the travel permit - I'll have the insurance papers in my hand before I leave home and all I have to do is stick them on the window - I'll learn more about the bus during the 600 mile drive home - I've been looking for a bus for months now, and was aware of this one for most of that time, but was hoping to find something a bit longer - this one will do the job, I think, the price is right, and time has become a bit of a crunch as dryland racing starts at the end of this month - we might miss the first race as it is, but oh-well, we'll survive
 

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Years ago, I talked with a big-truck transmission shop about two-speed rear ends and was advised to stay far away from them. They are difficult for most folks to drive CORRECTLY, and they fail often and dramatically -- especially when not driven absolutely correctly.
 
Congratulations ... looks like you are close to getting that bus. It sure has been a long time for your search. I hope it all goes well.
 
Basically yes you can change the ring and pinion, and leave the planatary gears alone. Or change the whole carrier in the rear. Any idea of what rear it is? Eaton, Dana, model number etc?

Mine is an electric shifted Eaton with 5.14 ratio in high. Was in the Vermont and New Hampshire mountains last weekend and made good use of the 2 speed. Steepest grade was 12%, so got to do some split shifting.


don't have the name model of the rear end
 
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Years ago, I talked with a big-truck transmission shop about two-speed rear ends and was advised to stay far away from them. They are difficult for most folks to drive CORRECTLY, and they fail often and dramatically -- especially when not driven absolutely correctly.

thanks - I do have some experience with them - my daily driver was a 2 1/2 ton Mercury for a couple of years
 
Years ago, I talked with a big-truck transmission shop about two-speed rear ends and was advised to stay far away from them. They are difficult for most folks to drive CORRECTLY, and they fail often and dramatically -- especially when not driven absolutely correctly.


I don't doubt that they have had some problems but I would wager 90% of those problems were because the driver was unaware of the proper shifting technique or was never shown. I've driven a few and they worked fine. You just have to shift properly.
 
Many moon ago I worked for one of those"chemical lawn care companies" our fleet of trucks were early 70' c-60 Chevy trucks with 350 and 292 I-6 engines all with 4speeds and 2 speed rears all driven by people barely old enough to posses a chauffers license I worked on those trucks for over three years and in that time never had any problems with a two=speed axle I thought they were damn near "bulletproof". Gene
 
Still working on that?

....................any one?................


Hello sir, sorry it took 4 yrs. to repond :oops: Just joined. I was wondering if you were still dealing with this or better, did you solve the problem. I put a 350 in my 59 Chevy and it also windsout at 50 mph since. A split gear rear end was suggested (among too many suggestions). I was thinking of going down to an engine with less power and more torque, like a 327. Thoughts?
 

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