F700 Help
Thread Starter
|
New User
Joined: Feb 2009
Posts: 1
Likes: 0
F700 Help
New here, so I don't know if I'm in the right forum or not. I was wondering if anybody on here has experience with medium duty Ford trucks? Mine in particular is a 1995 F700, 7.0 gas, MT 643 Allison Trans. I'm currently getting around 5 mpg loaded or not. The rear end in this thing has a 5.86 ratio, and has the engine very wound out going down the highway (around 3000 just over 60mph). I don't haul that heavy of loads, so I think I would have plenty of power if I changed to a 3.9 or so ratio in the rear. I would think I could gain a couple mpg's if I could get the cruising rpm's down. I know its never going to be great, but if I could get up to around 8 mpg I would love it. My other concern would be if it would screw up the shift points of the automatic trans? I appreciate any input you guys can give me. The carrier swap looks pretty simple, and affordable (around $700), but I don't really want to do it if its not going to gain me anything.
Thanks
Thanks
FTE Leadership Emeritus
Joined: Jul 2002
Posts: 42,561
Likes: 423
From: Long Island USA
Is there a speedo gear in the tranny? Where does the PCM get the speed from? The tailshaft of the tranny? Or like the Superduty, from the rear differential? Does it have rear-wheel ABS (probably not, I'm thinking).
If it has a speedo gear, all you need to do is get the right speedo gear, and get the speedo reading correctly, and the computer should be able to deal with it.
Any chance of putting a two-speed rear in it so it's selectable?
If it has a speedo gear, all you need to do is get the right speedo gear, and get the speedo reading correctly, and the computer should be able to deal with it.
Any chance of putting a two-speed rear in it so it's selectable?
Thread
Thread Starter
Forum
Replies
Last Post
pgood1
1987 - 1996 F150 & Larger F-Series Trucks
8
Dec 4, 2013 05:12 PM
jroehl
Clutch, Transmission, Differential, Axle & Transfer Case
11
May 1, 2004 01:33 PM
