Have an '86 F250 4X4 w/ 4.10 front/rear end. Anyone have set of 3.55's (front & rear) for sale?

 

check the classifieds link on the top right corner of your FTE page

 

If you really want to swap gears...why? The 4.10's would allow for a bigger tire with less power loss, and the gain in mileage if the tire width is kept relatively close to stock should be noticeable. Changing to a slightly larger tire will give you the same benefits as changing gears, and less work. May have to change speedo gears to accomodate, or just do the math on the difference and drive accordingly.

 

Don't necessarily want to change gears, but my main concern it to INCREASE gas mileage. Currently getting 7mpg. What size tire would you recommend? Please advise what you mean by "changing speedo gears.:
Thanks!! Mike

 

If you are serious about wanting to change gears, i have a 3.00 gears in a '82 F-150 4X4. Rear axle is a 9" and the front is a Dana 44. I'd be happy to arrange a fair swap if you'd want to go to a 3.00 gear set up. I'm not convinced though that you'll get better gas mileage. Is this a highway use truck?? Towing truck?? Or??? The only way i think you'd save gas with the gearing is if you do a lot of highway driving with little towing (unless you have incredible horse power). The lower gears (4.10) provide better torque at starting off the line and with towing, and thereby puts less strain on the engine (saving gas).

I'm serious about a swap, if your interested......but again, not sure it will accomplish what you desire.

 

Thanks for the offer. The truck is used in a 50/50 Hwy/Tow useage.
Regarding the swap, I don't think I'd want to go that high. IF I decide to change,
I would like to stay around 3.55.

 

About the "Speedo Gears" comment...he was talking about putting on bigger tires and the Speedometer reading. With larger tires, for example, your speedo will say 45 and you'll be doing 55mph.

I'm kinda new at this, but one idea is horse power "add-ons". Like a k&n air filter, throttle body spacer, new headers, and free flowing exhaust. These modifications cause the air to flow through your engine 'system' ALOT better and will give a big boost in horse power, with no increase in burning gas. What this will does is give you more bang for the buck, and it will reduce the engine strain at start off and towing, THEREBY giving you better gas mileage!! (and much better 0-60 too). Initial costs could range from $500 to $1,000 for all those mod's. Considering gas prices, you'd get it back pretty soon though.

Another thought.....i would post a new thread with the heading "Need better gas mileage" and see what you get. Couldn't hurt......hope that helps.

(Also, found a web site that sells a air booster that improves gas mileage AND horse power. It's www.turbonator.com and it's only $70 bucks. I'm planning on getting one for mine. Basically it does what a Throttle body spacer does, but at a cheaper cost and easier installation.)

 

a set of 33's and 4.10's is about the same as 3.55 and 235/75's, but since yours is a 3/4ton your tire size should be a 235/85R16. But if you can go bigger, 35's will rub, but if you can find a tire in the 34" range you would be better off then changing gears.