1996 Explorer AWD problem

[greg1]

Took my car in for a sticker and needed 4 shocks, passenger tie rod and front tires. I put 4 new shocks in and drove my car to the mechanic the next day and drove fine. Mechanic put in new tie rod and put on 2 used front tires that I had. The car had 275/75/15's all around and the 2 used ones I gave him were 235/60/15. When I picked up the car, as soon as I got on the road I could hear a groan/whine noise coming from the front end and sounded like a big truck slowing down. The noise slowed down as I slowed down so I thought it might be the wider tires on the front so I switched them to the back but still have the same problem. Any ideas out there as to what it might be and WHY it started as soon as I had the tires replaced? There was a clunking noise coming from the front end while I would roll slowly forward prior to all this but I never had the whine noise. It pretty much sounds like driving a 4 wheel drive truck locked in 4 wheel drive on dry pavement.
Any help would be appreciated .
Thanks.

 

[Joe Dirt]

If you have a size difference on the tires, it will eat up the transfer case.

Those tires are nowhere near close enough to be on the same vehicle. You're running about 666 vs 797 revs per mile comparing the two.

I suggest you get them off the truck now, chances are with that much difference you may have already destroyed something. The AWD MUST have matching tires on it.

 

[jremington59]

Joe's right. I was told by Ford the truck will sense as little as 3/32nds diffrence in size and the truck thinks a tires slipping and transfers power. With that much you will do damage very quickly.

 

[greg1]

Sorry, I meant to say that the original tires were 235/75/15, NOT 275/75/15 and the ones i put on were 235/60/15 so they are both 235's but the 2 I replaced were 60 not 75.

 

[SoNic67]

The manual says clearly that on the AWD vehicle the tires should be IDENTICAL.
That means same brand, same numbers (all numbers) and same tire pressure.
Even if when not installed on vehicle they have the same external radius, once loaded with weight, they deform and their radius change. If they are not identical and inflated with same pressure, the 'deformations' will be different, so the radius will be different.

In your specific case the 'equal 235 numbers' meant that their WIDTH is equal, but the HEIGHT is different (because of aspect ratio 60 vs 75).

 

[my98nnj]

75 vs 60 is the height ratio of the tire. Exactly what we're telling you. Get them off, you need the same size tire on All 4 corners. You may have already damaged the transfer case if the noise remains. I would suggest you find another mechanic too, he should know better.

 

[Cranmaro99]

Yeah change the tires ASAP! Might have already done damage.

 

[greg1]

It is at the garage now getting the same tire size and brand.
Thanks

 

[obie]

I'm surprised that shop even put mismatching tires on an AWD. I'd suggest never going there again.