Got to go faster.

[Train-train]

I have a local truck shop that I have visited to get some ideas from. My bus has a 5.9 Cummins with 4.63 in the rear. They say they can find a better rear for me for six hundred including labor. They were thinking a 4.10. Wound this work for what I want to do?

[Elliot Naess]

You can make calculations in a jiffy with this:
http://www.idavette.net/tech/ratioc.htm

Simply go to that site and punch in any three of the four numbers, then hit "compute" for the fourth. Magic!

[phillbus914]

try one of these calculators and see how much that'll affect your RPM's http://www.corral.net/tech/gearcalc.html

4.63 to 4.10 doesn't seem much difference

[the_experience03]

In theory he should be able to hit darn near 80 mph at 2600 RPM assuming he has 10.00R20/11R22.5 tires. That's also not including any tranny slippage. I think 70-75 mph would be doable. That might be worth the $600. The $600 is parts and labor? If so you're getting a deal. I've done some rear ends for smaller stuff and by the time you get a master bearing kit, shims, and the actual gears you can be in it for $250. If you add in the $100-$200 labor (going rate on rear ends) and you aren't but a few bucks short of what they quoted you for a much larger, heavier rear end.

[CAMO-MONSTER]

I WANT TO SWOP THE THERD MEMBER IN MY GM T170 TWO SPEED REAR END
MOTOR CHEVY 454
TRANS NP465 FOUR SPEED
TIRES 9.00 X 20
REAR END GEARS ???????

DO'S ENONE KNOW WERE I CAN FIND A THERD MENBER THAT WILL LET ME
DO UP TO 75 - 85 mph ?


CAMO-MONSTER

[keith]

ok i got a 5.9 cunni with a at 545 with a478 rear and i want to run about 65to 70 and they say i can't turn it up ,,it runs right about 58 to 60 on the hiway ,now this is a 94 bb 5.9 12 vale pump i feel the need for some speed,,,, help or should i sell it,,, now this was told to me by 4 diff cunnins men ,you can't turn it up... HELPPPPPPPPPPPPPPPPPPPP

[Steve]

Originally Posted by the_experience03

In theory he should be able to hit darn near 80 mph at 2600 RPM assuming he has 10.00R20/11R22.5 tires.

And assuming it has the power to overcome drag and grade!

[phillbus914]

I have the same engine in my bus, with a 4.33 rear end and I can hit 77mph. Not sure what my RPM's are though since I have no tach. I'll tell ya though, I usually cruise 60-65 because fuel economy gets real bad above that.

[Joe Monstermaker]

Just make sure you're never going to need low gear to get moving on a steep grade with a heavy load... ever. Busses have low gears for a reason!
It sucks that the transmission doesn't have enough gears, with a wide enough ratio spread.

[CAMO-MONSTER]

Originally Posted by Joe Monstermaker

Just make sure you're never going to need low gear to get moving on a steep grade with a heavy load... ever. Busses have low gears for a reason!
It sucks that the transmission doesn't have enough gears, with a wide enough ratio spread.

THAT IS WHAT MITE BE GOOD ABOUT MY REAR END WHICH
IS A TWO SPEED.

BUT I STILL WOULD LIKE TO TRY AND FINED HIGHER GEARS
FOR MY DIFF.


CAMO-MONSTER