I have a stock 2005 XL 4.2 V6 5 spd 2wd. I put afetermarket black steel wheels on it last year, 17x7.5, along with 265/70/17 General Grabber AT2 tires. After that I started having front end issues including 1 bad front bearing (in the brand new rotors I had just installed) and, on the same side, bad lower ball joint. I also had a cracked coil spring so both front struts were replaced in the fall. This year both my front rotors warped. One of the rotors was just replaced this spring because of the bad bearing. I recently replaced the warped front rotors with Bosch quietcast lifetime warranteed rotors and Wagner Ceramic pads. I also went back to my stock wheels and 235/70/17 tires. I read on some forums and had a mechanic tell me that larger tires could cause excessive heat and warped rotors. Anyone have an opinion? I hate the 235 tires and would like something bigger...how big can I go without causing rotor issues?

 

First, about those ceramic pads .... ceramic is an insulator which means the pads do not carry the heat away from the rotors. Ceramic pads have become popular because of less brake dust and longer pad life, but the cost is shorter rotor life as they are forced to retain the heat. Most later model vehicles that come with ceramic pads come with larger rotors than the ones of days past .... but those same larger rotors will work great with semi metallic pads.

I know your truck maybe came with ceramic pads, but your rotors will be happier with semi metallic pads and as a side benefit, semi metalics typically have better cold bite when that deer jumps off the bank in front of you than say .... ceramics.

Yes, larger diameter tires, all else being equal, do work the brakes harder for the same exact reason that they take more power to accelerate the vehicle .... their larger diameter is like a longer lever.
Imagine a 9 lb. sledge hammer on a foot long handle, you can maybe grab the handle with one hand and lift the head by turning your wrist. Imagine same 9 lb. hammer head on a 3 foot handle and try to lift the head by just holding the end of the handle with a hand.

Besides taller tires, other things that are harder on brakes is not down shifting, not anticipating stops, driving fast into curves and braking, riding the brakes a lot, heavy loads, etc .....

 

I can appreciate the extra leverage caused by the bigger tires...along with the extra moment/weight being harder to stop. I guess my main question was whether those tires are "too big". I'll admit that, after placing them next to the stock 235 tires, I noticed the difference but I didn't originally consider it to be that extreme. I don't tow anything and I only haul occasionally. I downshift/engine brake as much as possible. I'm pretty sweet to my F150 since it's my daily and only transportation.

I chose the ceramic pads because I read that they dissipate the heat better than SM but it makes sense that they would not because ceramic is an insulator. I might throw on some SM pads next chance I get. $30 for new pads is much cheaper than new rotors and a lot less work (and iced tea).

 

I had LT265/70r17s on my truck for a couple years and had no issues, other than slightly lower city mpgs. And, being that they were LT's, they were heavier, too.

I'm also "2 taller in the front, and 3" taller in the rear. I went to a p245/70r17 for better mpgs.

If you want a little height, but not as big of a tire, try a 235/75r17.

Other than that, no idea why those larger tires would cause issues with your truck. I have the same truck, just a 2008 and didn't have a single issue from those size tires and I ran them for 30k miles.

 

I have a '08 that the dealer installed 265/70/17 tires. Stock size was 235/70/17 which are puny for this truck.
I have around 33k on original brakes, rotors and suspension parts with no problems. I did add a 1.5" AS spacer, but that was done when new and I did have a alignment done.
Did you own your truck since new? Also, how did you the the General AT/2? Those are on my short list when I replace my tires.

 

I bought the truck last year with 55k miles. The generals were on there for a year and I swear by them. I had the same tires on my 01 f150 for 30k miles plus until I sold it. I had Dueler Revos on that truck before that and I prefer the Grabber AT2s...especially for the big price difference.

 

Quite often, the reason for rotor warpage is overtightening the lug nuts. It is not always excessive heat.

 

I'm The grabber at2's seem like a great tire. I almost got them, but I've had really good luck with two sets of Firestone destination at's. Great in snow, awesome tread life and they're just as quiet as an all season tire on the highway.

Tried Cooper discoverer at3's between the two sets of firestones and wasn't impressed. Loud on the highway and didn't do nearly as well in snow.

Back to the OP's question though. Really doesn't makes sense unless you have some underlying issue with the suspension. The larger tire could wear your brakes down slightly faster (you wouldn't even notice), but they definitely won't have anything to do with bearings, ball joints or cracked springs. You're either extremely hard on the truck and drive it off road or as I said, there's an underlying issue. It's also possible that faulty parts were installed. If the nut on the bearing isn't torqued properly, it'll fail. The original coils on these trucks are also known to crack. I've read about it a few times.

How many miles on the truck and besides brakes, we're all the parts original?

 

That's also true. Even the manual says 150 lb/ft, which seems high. I only snug them up with the gun and then go around once more to be safe.

After having tires installed last time and then going to rotate, I've had to use a breaker bar to loosen the lugs as the shop way over tightened them.

 

sorry for the time lapse. I've been busy lately with an P0171 P0174 code. I did not own the truck since new. Bought it 10 years old with 55k so I don't know what was done to it. Had Autotire put the generals on but went back to stock tire size destination ATs after replacing the front rotors and pads with Bosch rotors and Wagner TQ ceramic pads... bought some Wagner TQ SM pads which I haven't put on yet. I was waiting for fall weather to make it a more comfortable job. The ceramic pads definitely slow the braking quite a bit and I'm a little worried about the heat to the rotor.

another note...I don't off-road, tow, haul too much, or drive this truck hard. I do a lot of city driving but that's about it. the cracked coil I attribute to a bad OEM part. The bad bearing was probably bad out of the box because I started hearing the noise not long after the brake job. I always use a torque wrench when tightening lugs but Autotire probably did not when they put the generals on. I blame the warping on cheap rotors. I got them from Napa but they were the cheapest option.

 

The destination at's are great tires. I've had two sets now and will continue to get them. Unless I live in a place without snow, then it would be the destination le.

I've read a lot about f150's and cracked coil springs. It doesn't seem that uncommon at all.

As far as the bearing, the nut has to be torqued perfectly or it'll fail. Had to have one replaced by a ford dealer while traveling a couple years back, failed 6 months later because they probably didn't do it right.