I have a 4.9l so the 300. It's my daily. All I'm trying to do I give it a more aggressive look. I currently drive it 100 miles a day, that's a lot I know. I'm a Pipefitter Apprentice so I drive all over Phoenix, AZ. I do majority freeway driving. I'm currently saving up for a car so I can make this truck a weekend pavement Princess. LOL. With all that being said would you recommend 31x10.5x15? Will that be too much for the 300? Should I wait to get bigger tires?

 

Gearing is really the single most significant thing you can do for these trucks. From the factory they usually were geared as if they did not even have overdrive. There are only pros to changing gears unless you consider cost a con. The cost is not cheap even if you do it yourself. At a minimum it'll cost at least a few hundred dollars or more to do it correctly. The cost at a shop could around $1000 or more depending what all is done.

I re-geared mine to 3.73 LS out of a 5.0 Explorer and rebuilt everything with new clutch pack, bearings, and seals. The biggest deal is setting up the ring and pinion gear. This is IMPORTANT or your rebuild or gear swap will be junk.

A 302 makes the least amount of low end torque so it sees the most benefit from lower gearing but don't gear it down too much or 1st gear will be useless and highway driving will be as if you don't have OD.

 

Check the code on the differential cover. Unable to say if the tire size is too much without knowing what gearing the truck currently has. If it has 3.31 or 3.55 it will be fairly good, and if it has 3.08 it will be fine, but if it has 2.73 it will be terrible. My old truck years ago had a 4.9 with 31s with 3.08 and it was fine, but I would have preferred 3.55. The inline 6 is not a high revving engine. I would no go more than 3.73 on an I6 truck.

 

I don't believe you said, but which transmission is in the truck?

 

Here's some info if you need it.

 

It's an automatic.

 

If you're going to regear it, and primarily be running it down the highway, 3.73 is probably your sweet spot between "street driveability" and "highway cruiser" with that transmission. I personally tend to gear down lower than most people, because I don't really worry that much about mileage on pickups. I'd go 4.11's, if it were *my* truck.

 

E4OD, with peg leg 3.08...OOO goody...

 

For the 300 I think that 3.55 would be the best gear. It makes power in the lower revs anyway.

My old 300 I6 truck was and E40D with 3.08 and I ran 31s for a few years. It was alright like that, but slightly less than desirable. Better than a 302 with 3.08. I had one like that too for a few years before re-gearing.