Ok guys, got my BFG's on this morning.... like the threat title says its size 285/70/17...... Took my truck over to the dealership right afterwards to get Speedometer changed around for this tire size, but ER ER ER! ERROR! ford PCM cant handle it! they called ford and they said this tire is to big for the f150!!! so i got charged $40 for them hooking it up and trying..... Those of you with these tires on Stock FX4 rims.... did you not change your PCM around or did you get a custom??? Tomorrow im going to the local truck shop (KC Customs) and their installing a new PCM with a custom tune for me so it matches my new tire size...... sound like a good idea? because its my only option other than taking this tire off and getting a 265 which i feel is way to small for this truck. Ok ranting is done sorry guys but this just pissed me off ...... besides the fact the service department looked at me and said "Hey this is going to void your warranty if you keep them on, and your transmision will fry for not changing the PCM," i told them about you guys having them on your f150's and they looked at me and said "Well their just taking a chance then of ruining their trucks and voiding their warrantys" BAH!


PS. does it matter which PCM im getting? im not sure which their ordering but its for my f150 and its just a custom tune with shifts and tire size and speedo etc etc..... Also what PSI do these tires need to be at? I love them way to much to part with them, Besides.... i started at 7:00 this morning to get these tires and now its 12:50! im late for work big time and my dealership just pissed on me!!! *shakes my leg* BAD DOG!

 

Ford can only calibrate for OEM sizes and the biggest is 265/70-17. I went from 255/70-16's to 285/75-16's and have never recalibrated my computer. My speedometer is off 5mph at 60mph. You can recalibrate it yourself with one of the aftermarket computer tuners like the Hypertech or Superchips tuners. You need to find another dealership to do business with if they are threatening to void your warranty for changes to a size only one inch larger than an OEM size.

 

I have an '03 4x4 King Ranch and put the 285/70/17's on my truck 10k ago. I never did anything with the computer at all. I really don't think it bothered the speedo that much actually. In reality, I think the factory calibrates the speedos faster than they are going in actuality, to try and slow people down. I have passed thru many a times with one of those roadside speed checks telling you how fast you are going and my speedo is usually within one to two mph. And that's at like 65-75 mph. And with the larger tires, sorry forgot to mention that. As for the transmission blowing, they're blowing, smoke right up your ****! The transmission could possibly blow if you had MUCH larger tires and did not regear. That I could see. But to say reprogramming the computer would fix it? Not a chance. Oh yeah, BTW, guess where I bought my tires? At my dealership!!! I have a good relationship with them and he matched the best price I found elsewhere. Down the road mounted and balanced for $754. He never said anything about warranty to me, and in fact, told me "Those bigger tires look pretty good on your truck". I'd search for a new dealer. sorry for the lengthy post but had to get my $.02 in here.

 

dont worry about it i appreciate your responce...... Tomorrow im going to go ahead and get that new PCM/Chip or whatever it is so i can have these tires calibrated with it, my speedo redone and get a little extra HP with it, This shop told me that they do buisness with another local dealership down the street from me, And that dealership sells F-150's with their programmed chips in it! brand new off the lot. So if they can turn the cheek away from it then thats where im doing buisness from now on. I got my tires from Tires plus for a pretty good price, final price was $896 for the BFG's and an alignment on my truck, i feel i made out pretty well..... Also i was wondering, Does the PCM control the electronic switch on the fly for the 4x4? just making sure if they end up changing things out that everything still works! lol. Thanks guy, This dealership were such *******s they lost my buisness 2 years ago with buying vehicles (have bough 2 vehicles since then from other dealership) AND now theyve lost my buisness for aftermarket parts and service. *spits on them*


Edit: Here's a link to my other thread with pics of the BFG's. 56k warning

 

Truck looks good with the larger tires. Did you crank your torsion bars up? I never did that with mine. I like the look of it being more level. My concern is I pull a travel trailer with my truck and I don't want it squatting down in the back when I tow. Probably wouldn't be a problem because I have an equalizing hitch but that's why I haven't done it.

As for the 4x4 switch I don't believe the reprogram will do anything to it. Don't have any experience with that but I can't see where that would make a difference.

Good luck with the new PCM and let us know how it works out.

 

Torsion bars remain stock level.... should i have them cranked up? Thanks for the compliment i think it looks 100% better with those bulkier tires than the weiner tires ford has for stock

 

No need to raise them with this size tire. Mine are fine. It just looked more level than stock. Must have been the slight incline in your driveway. Personal preference if you want to raise them or not. Your truck looks good the way it sits in my opinion.

 

My local Ford dealership has a brand new F-150 sitting on the lot with 35" tires mounted on stock wheels and I guarantee if you buy it you will get your full warranty.

My Gallery
https://www.f150online.com/galleries....cfm?gnum=6311

 

My local Ford dealership has a brand new F-150 sitting on the lot with 35" tires mounted on stock wheels and I guarantee if you buy it you will get your full warranty.

My Gallery
https://www.f150online.com/galleries....cfm?gnum=6311

 

Oh, I forgot to mention when I bought my truck in 2001, the dealer purchased my OEM tires from me so I could purchase larger tires. They couldn't get BFG's at the time so I had to purchase them from my regular tire guy. That was over 40,000 miles ago. Also, what size were your OEM tires? If they were 265/70-16's, the new 285's are only an inch taller so your speedo won't be off much.

 

old tires were a 265/70/17 these are a 285/70/17, its rediculous that they threw such a fit lol

 

Does anyone know if a 285/70/17 on the new body style XLT 17" rims will clear? Oh I have the 2" leveling lift as well. Can I go any bigger in tire size? Also, does anyone know, if I get a used set of 04/05 18" FX4 rims, what is the biggest tire I can run? Thanks for the input....

 

I am running Goodyear MTR 285/70R17 on stock wheels on an 05 SuperCrew with a 2 inch EZ Lift leveling kit. There is tons of room, I wish I had gone to a 305/70R17.

My Speedo was fast with the stock tires, by 3-4 mph at some speeds. I checked with my new larger tires and up to about 30mph the speedo is about 1mph faster than my GPS speed. After 30ish it is dead nuts with the GPS.

My odometer is about 5% slow though, for every 20 miles on my odometer I travel 21 miles by GPS.

 

I totally agree with you man. The dealership will treat you well so long as you don't have an attitude of "I know you're trying to screw me" when you go back to them. As my service guy told me when he told me I needed new tires - "Look, I know and you know that you will need tires soon. When you do, I'll let you know what will look good and will call all the big tire stores around town for you and match the lowest price I am able to find. Don't worry about calling those places - I have them on speed dial and will do the legwork for you." He also told me that lunch was on him if he had to lower his price to match someone else's. Judging by the fact that I have HIGH respect for ALL of them over there, I can ABSOLUTELY see him holding up his end of the bargain if he found a cheaper price.

I never took my truck to the dealership during the first 50,000 miles of her life and have been screwed over WELL MORE THAN ONCE by those pull and chug oil change shops, tire places, and the like. As soon as I re-discovered the dealership, things have been a no brainer ever since. My service guy even remembers me when I know he has hundreds (maybe thousands) of clients. Kinda makes you feel good like you belong to the family. None of the other places remembered me - they were too busy screwing up my truck and charging me less for MUCH LESS service.

Your "stealership" people are good people - usually much better than any other place where the oil change is only 3 bucks cheaper.

 

Maybe it's a Texas thing, but I gotta agree with thereisnospoon.

The deealership people are used to people getting p*ssed off all day, so if you approach them with a good attitude, they'll generally more than willing to help. I've had a couple Fords, dealt with a couple Ford dealers, and I can't say that I've ever left mad. I wish I could say the same for my experiences at [insert quick serve place name here].

I've tried to find every way possible to save a little here & there, but I know the dealership tries. I appreciate that.

Do they have to cover their butts occassionally? Yeah, but who doesn't. I would try a different approach with the service manager. Ask him from a newb position to explain the tires/tranny/pcm relationship. He might even know a few folks to refer you too.