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BU Deer Hunter
01-12-07, 09:31 PM
I have a 2006 F-250 4x4 Crew Cab Diesel. I currently have 285 tires with 17'' rims. How big can I possibly go without changing the rims or lifting my truck?

WS6bear
01-12-07, 09:35 PM
u couldnt put 20's on a 17'' rim if thats what you mean, as far as width, you should be able to put up to a 315 on them

CammoTX
01-12-07, 09:38 PM
One thing you need to consider is that the bigger the tires, the worse your gas mileage.

CammoTX
01-12-07, 09:42 PM
One day back in high school I was reading truck trader and I saw a Suzuki Samurai that had 44' Super Swamper Boggers. The guy had rebuilt his front end (put a 350 engine in it) and gave it a 16'' suspension lift.

It was the most badass mudding vehicle I had seen in my entire life.

Wacoso
01-12-07, 09:49 PM
One thing you need to consider is that the bigger the tires, the worse your gas mileage.

Not like an F-250 is etting any mileage.

nein51
01-13-07, 09:30 AM
I have a 2006 F-250 4x4 Crew Cab Diesel. I currently have 285 tires with 17'' rims. How big can I possibly go without changing the rims or lifting my truck?Depends. Are you on the stock wheels?

PS - I am actually a professional at this.

jstins
01-13-07, 09:40 AM
I went to a larger tire and now I travel at 10% faster than my seepdometer shows.

Ghostrider
01-13-07, 09:41 AM
IMO 285's are a good enough size tires for 17's....I would go to far away from stock b/c you will see a different ride...also go with a good street tire...don't get the offroad crap....they get too much road noise and mud gets all in the grooves and has made it worse for me than road tires....i also like my new cooper tires.

oh, and if you go larger, make sure the tire isnt sticking out...it'll throw mud and rocks all over your paint

nein51
01-13-07, 09:42 AM
I went to a larger tire and now I travel at 10% faster than my seepdometer shows.That can be calculated and you could even have the speedometer recalibrated at a place like Hollywood Speedometer.

If you have a 10% speedo error you must have gone MUCH bigger than stock.

Ghostrider
01-13-07, 09:43 AM
nein, that is what I was thinking....like 6"!

jstins
01-13-07, 09:57 AM
That can be calculated and you could even have the speedometer recalibrated at a place like Hollywood Speedometer.

If you have a 10% speedo error you must have gone MUCH bigger than stock.

245 to 265 I think. I don't know much about tires. I love having the larger ones though.

nein51
01-13-07, 10:20 AM
245 to 265 I think. I don't know much about tires. I love having the larger ones though.That shouldnt cause a 10% speedo error.

245 or 265 is the width in mm.

jstins
01-13-07, 10:22 AM
They are taller too. Like I said, I don't know much about tires. I have an 04 Ram. I may have gone from 16" to 18"

nein51
01-13-07, 10:46 AM
They are taller too. Like I said, I don't know much about tires. I have an 04 Ram. I may have gone from 16" to 18"AHHH, well THAT makes MUCH more sense :)

LIB,MR BEARS
01-13-07, 12:31 PM
see if this site will help http://www.dakota-truck.net/TIRECALC/tirecalc.html.

If this one doesn't, type in "tire calculator" on your search engine. There are several on line to choose from and many will give you your speed variances.

nein51
01-13-07, 01:12 PM
see if this site will help http://www.dakota-truck.net/TIRECALC/tirecalc.html.

If this one doesn't, type in "tire calculator" on your search engine. There are several on line to choose from and many will give you your speed variances.Those are great for speedo.

They do not help you any with rim width/load carrying capacity and those issues are a LOT more important than speedo.

DONNIE D
01-13-07, 01:23 PM
Depends.

PS - I am actually a professional at this.I never you you wore these. I was sure you were not old enough. I heard Pampers was coming out with some new adult ones, but I never go on that aisle to shop. Kinda scares me.:lol:

nein51
01-13-07, 01:29 PM
I never you you wore these. I was sure you were not old enough. I heard Pampers was coming out with some new adult ones, but I never go on that aisle to shop. Kinda scares me.:lol:Only on days with mens and women's bball playing at the same time, I am scared of moving for missing something :)

DONNIE D
01-13-07, 01:32 PM
^^^ wats up???

LIB,MR BEARS
01-13-07, 01:34 PM
Those are great for speedo.

They do not help you any with rim width/load carrying capacity and those issues are a LOT more important than speedo.

here is one that will give you tire dimentions http://www.powerdog.com/tiresize.cgi. I think you can take this info then and go to brand web sites to determine carrying capacity.

deltbear
01-13-07, 02:22 PM
Just go a size or two up and get BFG all terrains and you are set. Never fails.

Wacoso, you would be suprised at the kind of mileage a diesel can get if you have a light foot on the pedal. Probably close to 20mpg in the city.

BaylorGuy314
01-13-07, 03:08 PM
You can get 35x12.50s on there or the equivalent in a metric for a 17" rim.

I put 36x14.50 on my 97 F150 with a 3" body lift and a 2" suspension lift (changed out the stock torsion bars with Chevy 2500HD torsion bars in the front and went to a 4" block in the rear instead of the stock 2").

The truck drug a bit and ate more gas until I switched out the 3.55 gears with 4.56s. That solved both my sluggishness and gas issues, but it did run about $800 ($400/axle).

35s won't be too bad on a diesel though. It won't make a significant difference as far as gas is concerned. And diesels don't exactly blow off the line as it is, so I'm not sure I'd worry about changing the gear ratio.

The biggest concern for ride quality is not tire size but the type of tread. How aggressive are you going to go?

nein51
01-13-07, 04:55 PM
You can get 35x12.50s on there or the equivalent in a metric for a 17" rim.
You shouldnt mount a 12.50 on a stock Ford/Chevy wheel it is FAR too wide for any of them and would exceed the stock wheels carrying capacity (and I mean wheel, not tire).


The truck drug a bit and ate more gas until I switched out the 3.55 gears with 4.56s. That solved both my sluggishness and gas issues, but it did run about $800 ($400/axle).
4.56 gears would make the thing a BARGE when it came to gas, you sure you didnt go the other way? On the highway a truck with tires that size and 4.56 gears would be turning like 5500 RPMs at 70 miles an hour, not good for gas or the transmission.


The biggest concern for ride quality is not tire size but the type of tread. How aggressive are you going to go?
Nothing funnier than watching a kid with a lifted truck riding on bias ply TSL Thornbirds. You can hear it coming from a mile away, they get awful mileage and bias ply tires SUCK.

BaylorGuy314
01-13-07, 09:08 PM
You shouldnt mount a 12.50 on a stock Ford/Chevy wheel it is FAR too wide for any of them and would exceed the stock wheels carrying capacity (and I mean wheel, not tire).

Kinda sorta. I used to work at a tire shop and we would commonly mount 315/75 (a 35x12.50 equivalent) on stock Ford rims. However, a wider rim IS recommended because mounting a tire that wide on a stock 7" wide rim makes the tire buldge and will wear it out much quicker. It's also easier to lose a bead if the pressure gets low. I wouldn't recommend a 35x12.5 (or equivalent) on a stock rim (I would recommend 285s or equivalent), but you can do it if you want. A shorter but wider tire will probably look better as well.



4.56 gears would make the thing a BARGE when it came to gas, you sure you didnt go the other way? On the highway a truck with tires that size and 4.56 gears would be turning like 5500 RPMs at 70 miles an hour, not good for gas or the transmission.

My RPMs decreased considerably on average, which was the goal. With the stock 3.55s, my truck was constantly dropping into a lower gear to maintain higher speeds (60+) or make it up a very slight grade. (Driving back from Waco to Houston, I would spend more time in 4th gear than 5th when I had the 3.55s.) While the 4.56s made it idle a couple hundred RPMs higher than with the 3.55s in a given gear, I spent more time in overdrive with the 4.56s than the 3.55s. What you are saying makes sense, but it didn't work out that way for me. My around town gas mileage went down, but my highway mileage went up enough to compensate.



Nothing funnier than watching a kid with a lifted truck riding on bias ply TSL Thornbirds. You can hear it coming from a mile away, they get awful mileage and bias ply tires SUCK.

Absolutely on all counts.

One of my buddies in high school had thornbirds on his tacoma and when heading down to Crystal Beach (near Galveston) one day, he literally started throwing the nubbs off the sides of the tires. They may be good mud tires (debatable, IMO), but they really suck for street driving. All bias ply tires suck unless they are used strictly for offroad.