i got a 2006 5.4 xlt with 3.55 limited slip and i just put 33's on and i was looking to jump up to 4.10's.. what am i looking at spending for all the parts and who knows where a descent place price wise for good parts

 

anybody....

 

parts can easily run 800 bucks, labor extra. ronsperformance on ebay has good prices.

 

personaly i wouldn't regear for 33's. now if you plan on going bigger tire wise later then you could go ahead but i wouldn't pay that much for such little gains.

 

Now, it's a different setup, but I regeared to 4.10s in my 08 XL 4.2L 5speed and did not like it at all. It destroyed my MPG (13-14 mpg highway) and gave very little noticable performance gain, so I ended going down to 3.55 (3.31 was stock). Now, in my 96 Mustang GT, 4.10s made an incredible difference, but not in the F-150.

 

Just curious why did you not go down to the 3.73? I have a 2007 F150 XL 4.2L V6, 5 speed, with stock 3.31's I have been considering going to 3.73's as well as putting in a diff temp gage.

Jon Bradshaw
Clarendon, TX

 

I went back down to 3.55s to get the highway cruising RPM back down closer to 2000, as it was turning more than 2500 with the 4.10s, and as I said, I was getting 14 mpg on the highway. I didn't think dropping to 3.73s would be enough of a decrease, so I went with 3.55s and I'm happy with them. Mileage is back to 18-19 highway, average 17.5mixed, better pull than stock, and I was able to easily get the speedo back into calibration without buying a tuner. Now, do note that I have 275/65 tires on FX4 rims, which are 2" taller and significantly beefier than the stock Hankooks, so those affect the truck's mileage, performance, and overall end ratio (effectively reduce it), so your experience may vary.

 

Expect when it's all said and done to cost around $1800. That is most likely the high point though. So if you budget for that and come in low, then you have some extra gas money!

 

$1800? Wow, that seems really high! I had 2 sets of gears (and a Detroit Tru Trac the first time) installed for a total of about $1500. Parts are usually about the same, so the difference must be in the labor.

If I had only done it the first time, with the gears, diff, and new bearings, it would've only been $1050, and $450 of that was the Tru Trac.

 

your just 2wd right?? it cost more for 4wd two diffs to deal with