ok, so i had a nail in my tire, went to sears (my first mistake) and got it patched. while i was there i figured id price a set of BF Goodrich All-Terrain 33x12.50's just fr future reference. we got to talking and he told me that if I had ABS on my truck, which i do, an 01 Ranger, and I went to a bigger tire like a 33, the ABS sensors would be all out of wack and it may not run correctly or even lock up my brakes?! He told me the ford dealer could recalibrate the sensors for the larger diameter tire but could only do it 3 times before you had to replace the ABS computer and that was like $2000!......So in other words, for those of you that go from 33's to 16's then to 33's then to 16's depending on the weather or whatever, you could only switch 3 times. this is interesting to me cause I have never heard anything about messing with the ABS computer after you put a bigger tire on. Has anyone ever heard of this or had to do it? cant you just do the body lift, get the wheels you want, make sure they clear the rotors, mount your 33's, balance them, crank the torsion bars if desired and be done? whats all this ABS computer crap?!

 

I have never heard of that, I think he was blowing smoke up your @ss. I went from 245's to 265's then to 33x12.50's with no problems with my ABS ever. No random lockups or it not working like it should.

 

i went from 31s to 32s and the tranny wouldnt work. this is what im telling people, it is a possibility, get your dealer to reprogram it.

 

I have 35's on my truck with no problem... the wheels speed sensors will be reading a different speed than you are acualy going but it wont make the abs not work or the brakes lock up..
Now if you put two different size tires on it the abs wont work.. ie 31's in front and 33's in rear..
because the abs speed sensors are reading 2 different speeds which tells the abs computer that something is wrong and the light will come on and abs will be disabled..

 

it might take a while for abs to respond to the bigger tire. when i went from 29s to 32s the brakes themselves felt wierd, not just longer stopping times.

 

No that can't be right. The ABS does not recognize what size tires you have, because the wheelspeed sensor is not on the outside of the tire. If you run different sized tires front and back, your gearing will be F'd up, especially if you have 4wd. The rotation distance will be different, and your gears will "wind up", I believe. Sorry, what I'm trying to say is that it is something else other than different sizes of tires that would trip the ABS. Different sized tires are unrecognizable to the ABS. 33s do require a different amount of torque than smaller tires though.

Aaron

 

thats interesting...

after i got my 32s ... or....large 31s....whatever...anyway, since i got them, my abs and breaks seem screwy

 

im pretty sure abs uses rpm and speed sensing. if a speed is obtained at a different rpm then it says something is wrong and doesnt know wut to do.

wut i dont understand is why you can only reprogram 3 times. dont make a licka sense.

 

the abs works off of wheel speed... there are 3 wheel speed sensors on rangers
1 on the left front 1 on the right front 1 on the Diff in the rear ..
If you run 31's in the front and 33's in the rear the wheel speeds are different and will cause the abs light to come on and the abs to be disabled!..








this is the last comment I am going to make ... everyone wants to argue with me about this stuff... I do this everyday..thats is my job!!!!

 

I have actually had this happen. After I got my 32's I have had my brakes lock up on me for no reason. Like one time it happened when I was backing out of my drive way. I went to brake and they locked up. I dont know if it was caused by the bigger tires, but just thought I would share that I have had it happen to me several times for no apparent reason.

 

theoretically, i can certainly understand the possibility considering the different factors involved and the sophisticated technology being employed in a more complex manner as science advances...

but in this particular scenario, i havent personally heard of any instances similar to having abs problems caused by larger-than-stock tires.

 

Im gonna get bigger tires... and if they lock up, im gonna pull the fuse

 

who really needs abs anyway?


i went from 245/75-r16 to 285/70-r16 on my rubicon and didnt have any brake issues i didnt have before.

then again, my rubicon didnt have abs, even though it had 4wheel discs. can you say... street surfing?

 

ok, let me chage it up a little. i want to run 15x8 inch wheels and 33x12.50 tires....does that help the issue or make it worse for everyone? lol. i reckon im gonna call the ford dealer tomorrow and see what they have to say. im starting to get a little disturbed about how much trouble a body lift is slowly turning out to be

 

its nice to have a mechanic in here though. if he hasnt seen that before, maybe it doesnt happen? lol.....i hope.

 

Treff, you say you know what you're talking about, but seriously, explain to me how it can tell your wheel speed? Why do you think people report an innacuracy when they move to larger tires? The sensors are located on toothed gears, and when the gear makes a revolution, a small electrical signal is created(due to the magnetic fields) and sent to the computer. the computer is set to think the tires are stock size(either 29 inches or 31 inches) and does calculations on how many times it gets the signal.

I agree with this but for a different reason. I believe that having larger wheels causes binding since the tires would have to "chirp" because the front ones are going different speeds than the back ones. The sensors must either be able to detect an imbalance in wheel speed cause by the different tires, and the binding effect they should have in the differential. But the sensors do not measure Tire speed, they measure rotation(not of the wheel) and use a formula including the supposed size of tires to find out the vehicles speed.

All you said were two obvious facts, that vehicles and wheel speed sensors, and that different sized tires will cause ABS problems. A man who's forgetton more about vehicles than you've learned(although he has many years on you also) taught me, and I'd be glad if you'd tell me how I'm wrong.

Aaron

 

I never said anything about you being Wrong!
All i said is IF you change tire size on the rear and not the front the rear wheels speed sensor would be sensing a slower speed than it is acualy going...causeing an ABS problem...
If you had ever hooked a scanner with an ABS package you can read wheel speeds per wheel !
I have said enough! who cares!

 

Ok yah I believe all that. And to the "who cares!". You responded, so you?

Hey umm one question though, If you can use a scanner with ABS package to read wheel speed, would it read differently if you first had 29 inch tires on, then second time you put on 44s? That's what I'm arguing, its not "wheel speed" as most people say. Since a lot of people here have non-stock size tires, it is an innacurate term.

I agree though, any idiot stupid enough to run two different tire sizes will have ABS probs.

Aaron

 

hahahaha

 

Do you not realize that "wheel speed" and RPM's are basically the same thing? I am a woman and I understand that...I don't even work on cars and this makes sense to me...

You are both saying the same thing. Is there some reason that you have to go and make things so complicated??? That is a woman's job.

 

if you run larger tires the sensors will read like the stock tires are still on it..
but the speed will actually be wrong! like your speedo will

 

Thanks Mark!

 

wheres all the damn pwned pics...

Im gonna go repsond to threads pulling answers out of my ***.. brb