f-250s have the sterling 10.25 axle (comparable to a Dana 70) in the rear. payload and towing are significantly higher. manual transmission is a borg warner ZF-5 rather than the Mazda tranny.

 

Don't forgett that he has the C6 3 speed, no overdrive, I dont know how much of a difference that makes but it sounds like it might not have hit you right away. I have a buddy with a 89 F-250 with a 302 and a mazda 5 speed. So the ZF-5 was not the only standard tranny offered in the 250.

 

The mazda was used on the 302s and possibly the 300s but..the ZF was on the bigger engines. I'd only recommend 4.10s if there is a ZF manual being used, or an automatic with overdrive. The reason you guys are getting 9ish mpg is because of the C6 not having overdrive. That totally sucks gas...I have 35s and I just put my 32s on for a lil bit and I went from 2050 rpm to 2240 at 65 and i lost a fair amount in gas mileage. So imagine the difference between 2100 rpm and 3000. lol

 

Don;t worry, once I'm done my engine/wiring/computer swap I'll get better mileage than even you <grin>.

Well, maybe not at WOT.

 

phatpharm:

Yes, I understand he has a C6 with no overdrive. carpe_diem agreed, since he has the same setup. I did the calculations, and to be turning that rpm with factory tires (or even 33s) you'd have to have 6.50 gears, and no one would ever have 6.50 gears unless they had 44 inch bogger or 46 inch michlins...

 

Ok sorry, I thought I'de double check.

 

I was thinking to buy another beater truck, but can't find one. Soooo I get a fairy good shape one from eBay. It is a 1996 F-150 4x4 with 130K. Too bad it is V8 5.0. I wish it were 4.9 I6, but oh ...well.

Here is a pic.



Later,

 

I have the 351. For towing, you will be much happier with a diesel or a 460. I wouldnt want any higher ratio than 4.10 in a 4wd with a 351 unless it was a Bronco or a half ton shortbed. Mine has 3.55 and its a dog. Im planning to go to 4.56 to get more torque for towing. The truck barely gets out of it's own way around town or up hills. It's really embarrassing to be passed on the hills by every gutless 4 cylinder econo box on the road. A 6000 lb truck should never have come from the factory with an engine this small and gears this high. My 33" tires dont make the problem any better iether. Get the bigger engine, you wont be disappointed. If you want better mileage, get one with overdrive or get a diesel.

Sorry, my computer hadnt updated and I didnt see your post about buying the new truck. Looks real nice, hope it serves you well.