|
Trans and diff ratio help
I'm ordering a new Peterbilt 335 single axel truck with the 6.7 cummins in it. Its replacing an older under powered ford with a 370 gas engine in it. The ford also was geared too low for the highways etc.
I told them I want to cruise at 60mph and I was offered several trans. diff combos. I want a 6 speed manual trans in it. So right now it was suggested I go with the 6 speed fuller fso6406a trans and a rear axel ratio of 4.88. The salesmen says it should cruise at 60mph and aprox 2000 rpm. It has the 6.7 300hp/2600rpm 620lbs of torque engine in it which should be plenty of power compared to the old truck. The truck will be used to deliever hay so half the time it will be running empty back to the farm. I just want to be sure it won't be reved out like my old truck always was etc. Does 2000 rpm or there abouts sound about right for this truck and engine? Does anyone know of a web site where you can plug in your tire size trans ratio's and diff ratio to come up with road speeds? thanks |
Do you know what model of engine it is? Not the size but the mode like a ISC or somthing. I think but don't hold me to it the ISC a 315HP had the HP @ 2100RPM so I think 2000RPM ought to be alright for that small of a moter.
|
Originally Posted by Mack2
Do you know what model of engine it is? Not the size but the mode like a ISC or somthing. I think but don't hold me to it the ISC a 315HP had the HP @ 2100RPM so I think 2000RPM ought to be alright for that small of a moter.
Well they call it the Paccar PX-6 300/2600 300@2600 620@1600 on the spec sheet. The Paccar of course is just a renamed cummins etc. They have some kind of deal worked out Paccar and Cummins. The truck is to be built next month a 2008 model. So I assumed it was the latest engine the cummins has to offer. On the other quotes I got from other compaines the cummins engine was always called the cummins ISB 6.7 engine rated at 260hp@2400rpm and 620lbs torque. The peterbilt quote rated it at 300hp@2600 so I don't whats the diff or if its the same egine or what. |
Most likley the same moter just Pete has the HP bumped up on it.
Isn't 620lbs of torque a little low. I mean thats not much more than what a Ford F350 has is it. |
Re: Trans and diff ratio help
Originally Posted by Hayman
I'm ordering a new Peterbilt 335 single axel truck with the 6.7 cummins in it. Its replacing an older under powered ford with a 370 gas engine in it. The ford also was geared too low for the highways etc.
I told them I want to cruise at 60mph and I was offered several trans. diff combos. I want a 6 speed manual trans in it. So right now it was suggested I go with the 6 speed fuller fso6406a trans and a rear axel ratio of 4.88. The salesmen says it should cruise at 60mph and aprox 2000 rpm. It has the 6.7 300hp/2600rpm 620lbs of torque engine in it which should be plenty of power compared to the old truck. The truck will be used to deliever hay so half the time it will be running empty back to the farm. I just want to be sure it won't be reved out like my old truck always was etc. Does 2000 rpm or there abouts sound about right for this truck and engine? Does anyone know of a web site where you can plug in your tire size trans ratio's and diff ratio to come up with road speeds? thanks |
|
| All times are GMT -12. The time now is 09:51 AM. |
Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved