royboyz

I'm looking for a recommendation to go with either a 3.55 or a 3.73 axle on my F150 order. I've read some posts on the forum but looking for your recommendation on my setup.

2016 F150 Fx4 supercrew 5.0L 5.5' with 2.5" level and 33" tires. The majority of my driving is 90km/h (55mph) hiway with the odd 500km roadtrip doing 120km/h (75mph). Tow a 2500lb boat but very rarely so any would do.

From what I can tell RPM with the larger 33" tire size and the 3.73 might be pretty close to a stock 3.55?

Appreciate your advice on fuel economy difference if any really? and also don't want the RPM's up too high for cab sound with an aftermarket flowmaster american thunder exhaust for drone. Thanks in advance really appreciate your opinions.

Scrappy Doo

iTrader: (1)

Your fine with either.

gymratt

I would go with the 3.73

royboyz

Thanks guys. Would i expect to see much if any fuel mileage difference with the 3.73 and 33" tires over the 3.55 axle? I'm doing all hiway driving.

PerryB

As tall as the 6th gear overdrive is, I doubt there'd be any measureable difference in mpg. Also, with the low (4.48 I think) first gear there's no practical advantage to one ratio vs the other. If given the option between two identical trucks, I'd choose 3.73. Otherwise I wouldn't worry about it. The broad gearing spectrum of the 6 speed greatly diminishes the significance of the rear axle ratio.

royboyz

Thanks very much guys for your opinion. I just got the order in with the 3.73 and the dealer found one. All set.

PerryB

Ok, you know the drill. When it gets here, pictures or it doesn't exist.

royboyz

Will do! I can't wait to get it!

royboyz

Got my pickup time at the dealer is Friday afternoon so I'll get some pics up on the weekend. Friday can't come soon enough! In the meantime here are the details.. just added to the signature

5.0L

PerryB

What color?