likefastboats
 

what engine do you have in your 650 ? Tim

fixx
 

why would that be hard to believe? we use to run big red @ 120 GPS going through new mexico..was a peterbuilt with a 600 cat turned up and a 18 speed,also pulling a 53' race car hauler and 500 gallons of fuel..

All I can say is I might be over the length limit but it would be PIMP!

http://cgi.ebay.com/ebaymotors/Ford-...75d3026e#v4-36

I towed my 29 fever with my 40 ft eagle bus . we were a little long , no big deal.

The power is not the issue, it's having long enough legs (gear ratio and tire size) to get a truck to that speed. You can put 1300 hp to the wheels, but if you don't have the legs the truck won't do 75.

I'll have to look at the tag to find out the diff ratio.

But it has a MD3060 Allison and both 5th and 6th gear are overdrive. It runs on 22.5 tires and 70mph is around 1700rpm going by the tach on the dash. Who knows how accurate that is.

I had it doing 80 crossing Texas at night and it had more left, but I'm guessing somewhere between 85 - 90 ish and it'd probably be done. I was hauling a 50ft trailer and no need to be stupid.

Plenty fast enough for me. I'm old now :D

did yours come with 22.5 wheels? I have 19.5 and my rpm sare 2300 at 73, I might try some 22.5 with some 255-70-22.5 about 3 inchs taller . my tires are 33.3 inch also I have 433 gears .

My diff is a 4.33 ratio too. So it says on the door tag.

Yeah it came with 22.5" wheels from new. I was told only the chassis's that were built to be car wreckers came with 19's and all the other Pete 330's and 335's come with the 22.5's.

It has really long legs in fifth and 6th gear though for what it is. I think top gear in the Allison is 0.65 overdriven and it locks the converter after that too.
I'd guess that probably accounts for the low rpm and decent fuel mileage at highway speeds.

Tire size is 255/70/22.5 like you're thinking of going to.

I'm going to try to find some 22.5 for it . I need 8 lug 275 mm bolt pattern , anybody have any ?

I saw these on eBay. The listing has ended but he usually relists. Just email him if your interested. http://cgi.ebay.com/ws/eBayISAPI.dll...m=251185243990