Just installed the new 4.10 Ford Motorsport gears in my truck. Installation was not as hard as anticipated it would be. Had no problems what so ever. No wine at all. As far as performance goes it is so much better. Before the truck would kind of strain with the 32" tires. Now it runs like a champ. Once i get the speedometer calibrated i will give you guys fuel milege reports and new rpm's.

 

Do you have the 5.4 or 4.6? Just interested to know if 4.10s add much punch with the 4.6 engine.

 

I am thinking of going to 4.10 gears and want to do them myself. Did you have a manuel to go by, or did you just learn as you went along. Also, how long did it take?

 

crain-
i have the 4.6L V8 and the power increase is tremendous. The 4.10's work perfect. But you have to remember that i have 32.5" tires too. I would not change to a 4.10 gear unless i had a tire bigger than say 30". Before my truck use to downshift alot and feel real sluggish. Now it goes almost effortlessly. It takes a big long hill to make the truck drop a gear now. As far as i can tell the truck runs about 300 more rpm at any speed than it use too. Awesome performance gain for only about 3 hours of work!

 

Got the official new fuel mileage test report today. Filled up and to my surprise i averaged 15.5 mpg compared to 13.8 mpg before i put the 4.10 gear in. I drive on highway and city. Before i changed tire size my truck got 14.8mpg. Very happy with the truck now! Hope this helps all of you thinking about changing to 4.10 gear!

 

I have the 4.6 with 4.10's and 295/75/16 tires. Since yours is a 97 and mine a 98 we can get away with a gear change in the VSS (Variable Speed Sensor). If you had an 18 tooth gear in there with 3.55 before the 4.10 you will need a 21 tooth gear. Will still be off a little but a lot closer then doing nothing. Can get gear from dealer parts. Enjoy

 

Increased mileage is probably due to not having to give it quite so much gas to do the same job, and you're probably now running mostly in the "sweet spot", i.e. max part of the torque curve.

Magnum

P.S. I guess 4.10s are another thing I need to save for.....

 

Just a quick Q on the mileage. Did you adjust the speedo for the taller tires before the gear change? Did you adjust the speedo for the new gears?

I don't doubt that you would have in increase in MPG's, as was stated above, the engine does not have to work as hard to get you moving from a stop.

When I put on slightly larger tires that changed my speedo, I checked the mileage, and it 'appeared' to really suck. Since my speedo was off, so was the odometer. I was just registering fewer miles on the odo due to the taller tires. Once I adjusted the speedo, the actual miles traveled was corrected and my mileage 'returned' to normal......

Just a thought, and if you have adjusted already, that's great!

 

Looking for gears? Check out my post here-

http://www.fordtruckworld.com/forums....asp?id=121744

 

Mitch150,
I did not change the speedometer before the gear change because i knew i would have to correct it again in a month. But it was only 5mph slower before the gear change and only 5mph faster now. This is not going to make drastic diff in gas milage. You have to take a long trip for the odometer to be about 20 miles off. EX. Took a trip to Florida and computer said 530 miles from my driveway to destination.Well when i got there i went just like the computer said and odometer registered right at 500 miles. Only 30 miles diff on 500 mile trip. I am going to correct the speedometer this week so it reads right. Hope this answers your ?