If you have an interest in understanding the math behind the charts, try this link: http://www.offroaders.com/info/tech-...ng/mph-rpm.htm

For a handy Java calculator: http://www.csgnetwork.com/multirpmtirecalc.html

For more detailed calculations on gear ratios: http://www.dfw-tx4wd.org/gears.html

 

hay those links were great I knew the first sights numbers would be a little off sense I will have a automatic trans. but thos simple calculations on offroaders.com worked great to figure out the gear ratios I would want. sense I am not going with huge tires but bigger non the less I will probably want to find a gear set in the range of 3.93 to 4.0. thanx again for the links I think if any one was to put 35s or bigger on there new f150 I would definitely recomend getting a 4.10 gear ratio unless they want there new big 4X4 to be gutless with no real low end torque which most big 4X4's want.

 

FWIW, you can get a new F-150 with 4.10 gears-- BUT, it is only available to those ordering the *Heavy Duty Payload Package -- which limits you to an eight foot box. Notice the gear set is 10.25", which is not the same as the (I believe) 9" set used in the non HD offerings. Note too, the 7-lug wheels.

Any of our Ford insiders here know if it is possible to get a truly special order done (non fleet), like a the HD package on shorter boxed truck? Silver or grey on a Lariat too?


*HD Package includes: 50 state emissions system; LT245/70x17D BSW A/S tires; high capacity 17” 7-lug steel wheels; specially tuned shock absorbers; heavy duty frame and 72 amp battery; spring, radiator and auxiliary transmission oil cooler upgrades, 10.25" gear set, standard 4.10 axle (Optional 4.10 Limited Slip), (Availability: Regular Cab Styleside 8.0’ box (145” WB) or SuperCab 8.0’ box (163” WB), XL and XLT, Requires 5.4L V8 Engine• Regular and SuperCab 4x4 require 35.7 gallon fuel tank

 

I too would have liked to have put that heavy duty package on my truck but coudn't for the same reasons you mentioned. I guess I will have to wait for the after market to offer the gear sets. might be a long wait.

 

If my research is correct, you can order either 4.10 or 4.56 the 9.75" (size of the F-150 5.4L ring gear -- the 4.6L is 8.8") sets right now! Found them for $252.50 a set here: http://www.adamsdrivetrain.com/ford.htm

Time to make that truck roll right on some tall meats!

Anyone wanting the specs for the new F-150 can see them here: http://www.fleet.ford.com/truckbbas/...50_04_221b.pdf

 

Well, I just got off the phone with Discount Tire and they're ordering the 285 70R 17 BFG Radial AT's for me. They're 7/10's of an inch bigger than the 32 inch diameter ford recommends but I'm going to go for it. So far I haven't heard of anyone doing this but I can't imagine there being a problem. I guess worst case, I put them on, they rub in the front and I'll order the Daystar leveling kit. I figure the kit with alignment will only be another $200.00 or so.

I'm still not sure exactly What tires are going to come with my FX4. I've heard General's, BFG's, Good Year.. Does anyone know for sure??? Discount tire is going to give me a credit for the stock ones. I'm hoping around $80.00 each depending on what comes with the truck. Apparently 17 inch tires are kind of an odd size..

 

that is interesting on that site selling the 410 gears for the rear end. don't I have to change the gear ratio in the front differental also. so they match. I know I don't want one set of wheels turning at one ratio and another set turning at another. that sounds like it could mess things up pretty bad.

 

jasonkola wrote:
You definitely need to be running the same gear ratio in the front diff, as you are running in the rear, should you decide to change gear ratios.

Speaking of gear ratios... Decided to look through the spec sheets to see what the auto tranny and tranfer case are geared like:

1st = 2.84
2nd = 1.55
3rd = 1.00
4th (OD) = .70

Low range on 4wd tranfer case = 2.64

With a final drive ratio of 3.73 (x 2.84 x 2.64) that gives the truck a 'crawl ratio' of 27.96 -- not too shabby for a truck. With the 4.10 rear gears, that would give you 30.74.

While looking through the specs, I noticed the HD Package is more than just the items listed in my previous post; the frame rail section dimension is increased from .120 to .150, which would suggest that the eight foot box is likely the only way the HD package trucks will be shipped.

Been looking at wheel and tire ideas and am bumming on the limited choices for the bigger (like 22" or 24") tires for the oversized aftermarket rims, as I was thinking more along the lines of Son of Tonka, than a low profile tired MacDaddy truck. Anyone able to recommend tires that for those sizes of rims, but with an aspect ratio of 65 (or possibly 75)?

 

Interesting thread, I have an added problem, I'm getting a lariet scab and it has 18" wheels. I want to put BF Goodrich All Terrain T/As on it and the only size in 18" is 285/65R18, about 32.6 inches...slightly above ford's recommendation as BHibbs mentions. They're also a bit wider.

Anyone think I'll have a problem with these tires on the 04?

Also, looks like I want to get the 3.73 gearing with these tires per RR_Triton's link, I want fair gas mileage, I won't be doing a lot of towing.

Anyone see a problem with that?

Thanks guys, LOVE THIS FORUM!!!

 

I doubt you will have any probs with that tire I am going to put the same outside diameter and width on my 17 inch rims when I get mine. I was pretty sure there would be no problem. but I ended up ordering me a set of the 2.5 inch front lifts made by daystar. I found a dealer in my aria who sold me it for only $130 dollars. once I put that lift on the front end I should be able to put up to 35's on my truck. but I won't get any thing bigger than those 32.8 inch tires on my truck unless I put a differant gear sets in the front and back of my truck and wider rims. that is all starting to sound like alot of money. so for now I will just with puting the 2.5 inch lift in the front and the 32.8 inch bg's on. you probably won't need the 2.5 inch lift with those tires. but I decided that lift was reasonably priced and leveled the truck out front to rear. and it allows for me to put bigger tires on in the future if I want. so I decided to put it in anyway.

 

Can I get the same price on the 2.5" lift??

 

I am sure you can. all I did is go to daystar's web sight and locate dealers in my aria. I emailed several of them asking for a quote on the lift kit. I only got two quotes answered and one was for $130 shipped to my door. I will be recieving it on monday or tuesday.

 

I think you broke the code Jason. Reminds me of the Jeff Foxworthy remark: "You know you might be a redneck... when the tires on your truck... cost more than the truck!!"

Seriously though, I have been doing a little searching around the net and I am amazed at just how pricey it can get, once you begin to consider the less mainstream wheel and tire upgrades. No doubt about it, a fair amount of the pricier goods are aimed squarely at the *bling-bling* market -- which ain't exactly my demographic. All I can say, is God bless America and our freedom of choice, but I will still likely retch like a 16 year old swilling Southern Comfort and coke, the first time I see a fully 'gangstad' 2004.

 

Thanks. Are you going to install it yourself?? I'm completely stupid about this stuff, so I don't have a clue how to do it, but I would love to set the front end of my FX4 SCrew up a few more inches to level it out... when it gets here, of course.

 

I don't know if I will install it myself or not. daystar says it is easy to instal and takes 1.5 hours to install. I will look at it when it gets hear and see if it has any instructions. and I will have to look at my truck when it gets here. the kits don't look real complicated. so I might be able to do it myself. I wont know untill my truck and the kit get here. if it looks too dificult I will have it put in. I don't want to do anything that will hurt my new truck. I will have to see I have quite a wait to get my truck though. my dealer says possably 2 to 3 months more. I am not sure if he was just trying to get me off his back. I hope it is not hat long a wait. I know people on here have had to wait 4 to 6 months for theres but they ordered before production on these trucks started. and of coarse the dealers get there trucks before us. my dealer has 17 trucks in stock now so mine should not be too far behind. I can't imagine it takeing another 2 to 3 months.