mercer transportation

I had a t6 for the farm once that had 4.55's. Didn't win any races but you could get out of the field with 80k on in 4th and not touch the accelerator.

 

Well I'm going to have have a shop cut off the band that is on the cac pipe anyways so while it is off might as well have them check the cac and recalibrate the gauges and check the ratios. I really like the idea of single screw with a lift tag axle, but would'nt I have to replace the rear drive with one rated for 23k gvr and a locker?

 

You wouldn't have to go with a 23K, just because of going with a lift and a single screw. But the 23K axle is an advantage as it allow more times you can run with the lift up. But even when your lift is down, its still helps the fuel economy as they is not gears in it.
Also if you go with a single screw that was orginally a single screw, it will have a locker already in it.
I'm looking for one my self. Problem being is finding a single screw with a 3:55 ratio. They are out there, just not as common as twin screws.
I'm going to order a new lift axle soon, install it and run with my orginal rear axle till I find a 23K single screw.
I'm betting this will put me over the 8 mpg mark. Another project which I'm looking forward to soon.

 

As far as traction running with a single axle and not a locker, all you would have to do to gain traction is raise the lift axle and this should be set up air valve inside the truck.
Not as good as a locker but would still work fine.

 

I will have get a quote on having that done, should probably either regear the rear drive or find a good used one with higher gears in it. Will have to save up a while for that though.

 

Your transmission is 99% a .73 od. Looking up on Roadranger Road Speed Calculator, it shows 65 MPH at 1600 rpm with a 3.90 rear and 22.5 lp tires..

As far as testing, like was said earlier, jack up one rear wheel, mark tire and drive shaft, except rotate tire TWO revolutions while counting drive shaft turns. Yours should be just barely shy of 4 complete turns.

 

Thanks Stranger, except I have the wide singles. 445/55/22.5 I believe. I do wonder if the previous owner swapped them out. They sure look shorter but maybe not.

 

I hope I'm wrong, but a .73 od trans with the size tires you have (491 revolutions per mile) running 65 mph at 1600 rpm calculates out to a 4.10 ratio. If that is the case it's no wonder your fuel mileage is down the tubes.


http://www.analysis-inc.com/reference/road-speed-calculator/

 

Yes I agree, unless my tachometer is off too. I sure hope so if not I am going to have to spend some coin regearing it! If I go that route I might as well take the front drive out and put a lift pusher in its place, my tractor is too short to put the drive in front. And I'm still going to have to regear it. Even with 1 drive and a tag it will still eat to much fuel, but will be better. I still have to fix the boost leak and I still believe it will be worth the money to replace the sensors in the emissions group, delta p, imap and about 5 others. Maybe I spent to much time reading rawze's posts.LOL. Thank you guys for all your input.
Rob.

 

Merry Christmas all Mercer drivers.
Hopefully everyone got home for the holidays.