When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
This is going to make me look like a moron but anyway, it happened to me.....
New tires put on 2005 4X4 Excursion Limited V10 last year. About 4000 miles driven total with about 3,000 of those miles pulling my 10,000 lb travel trailer. Never rotated tires during this time.
Brought the truck in for annual state inspection and the tech informed me that the rear driver side tire is an LT245 70R16 and all the rest are LT 265 70R16.
Tire has now been replaced. Rotated all tires putting new one and other rear tire up front. 4X4 has not been used other than to make sure it worked before purchase. Did any damage occur? What can I look forward to. There seems to be no mechanical problems right now. Something tells me there could be excessive differential wear, maybe.
I'm guessing yes. Very smooth turns. Not sure what code represents limited slip or locker. Sorry I did not mention that above. I never noticed any handling issues. I did notice that my speedometer was a little off at 70MPH, maybe 2-3 mph off but that may have nothing to do with it.
Check your drivers door sticker.... Under Axle you will see a number or a C with a number... If you have a letter C with a number you have limited slip. If just number you have an open dif.
If you have limited slip you have been adding some stress to it due to the tire size not being even in height.
Thanks Michael. The code is C1, so I have limited slip. What kind of damage? Mostly all highway speeds. It seems fine driving now so my guess is this is more of a life span issue, right?
I think you will be fine, tire height dif. Is very little, think of it as you were driving with one tire low in air. Time will tell, but if your not getting any noises now, I wouldn't lose any sleep over it.
BTW.... The speedo according to many here was calibrated at factory for 285/75r/16... I don't know why, that tire size was not an option... But when I went with 285's my speedo is now dead on thru 80mph, checked with my GPS.
Thanks for your help and insight. Still can't believe I never noticed. I even wash this truck myself. Once the guy told me, I looked at it and although they are pretty close in size, I wondered how I never noticed. He told me that it was the first thing he noticed as he was walking up to it.
BTW.... The speedo according to many here was calibrated at factory for 285/75r/16... I don't know why, that tire size was not an option... But when I went with 285's my speedo is now dead on thru 80mph, checked with my GPS.
You are right. That is odd. At around 65 - 70 mph mine is off by about 2-1/2 mph checked against my GPS. I like the way the truck looks with 285's. Maybe when these wear out..... Thanks again.
BTW.... The speedo according to many here was calibrated at factory for 285/75r/16... I don't know why, that tire size was not an option... But when I went with 285's my speedo is now dead on thru 80mph, checked with my GPS.
I'm pretty sure it was calibrated for 265/75/16. That doesn't mean that it is CORRECT with those tires on there. It is just about dead on with 285/75/16s on mine too.
Many car manufacturers calibrate the speedo off by just a little. Think it keeps them out of legal troubles. Makes you drive slower than you think you are.
Having different size tires just means the spider gears are spinning and revolving instead of just revolving which has no effect on the diff. They do spin a little bit due to tires not being exactly the same diameter anyway.
How many miles at a time did you pull the boat? With a limited slip even a little difference in tire height can cause problems towing something heavy long enough distances. I have had it happen to me so I know it can happen. It was my 89 F250 with 33x12.5 tires, one rear one was wore down pretty good and the other was newer yet. After a long trip I jumped out of the truck to hear my rear end boiling and popping. Not long after that I had to rebuild the LSD with new clutches.