Tire help

[BossChief]

I have a 2011 Nissan Frontier and I need to replace 2 of the tires on it and a friend of mine sold me 2 barely used ones for dirt cheap (100 for the pair) and let me know they aren't exactly the same size.

The stock tires are 265-70-r16

The ones he sold me are 265-75-r16

I brought them to Farm n fleet to have them put on and they called me back saying I really shouldn't put them on my truck because it can screw up my drivetrain being they aren't the same size as the other 2.

I had them hold off on putting them on and figured I'd ask you guys if that's a legit concern (the truck is 4wd).

I guess I've always had matching tires, but the deal was too good to pass on and if I need to, I can resell them.

[Baby Lee]

Originally Posted by BossChief

I had them hold off on putting them on and figured I'd ask you guys if that's a legit concern (the truck is 4wd).

The more sophisticated your system, the more important that specs are adhered to. This is particularly true with tire sizes and AWD/4WD. The transmission/transaxle is rotating at a certain speed, distributing power to the wheels. It's doing so expecting that each rotation will propel each tire a certain distance. If your tires are different sizes, they travel slightly different distances per revolution. If there's no slip feedback, that difference has to be absorbed by the system by either dragging the smaller tires a little bit to keep up with the bigger ones, or stressing the transmission/transaxle when each tire's distance to revolution ratio is different.

If you value your transmission, and do a lot of highway driving [where the differential builds up because the system can't correct like it could slipping on gravel or dirt or coming off the ground, I'd match the tires.

[Simply Red]

as long as there's clearance regarding tire height to bumper seam gap - you'll be fine.

[Simply Red]

your tire will have 5% actually less than that - increase in height - shouldn't be any other conflictions.

[Simply Red]

so here - if your truck is NOT lowered - let it rip - you'll be just fine, in fact - your truck will hook the road better (grip)

The more height - the better the grip. Due to gravity and physics alone.

[Simply Red]

Do you have any Football questions while I'm here?

[ptlyon]

Originally Posted by Simply Red

Do you have any Football questions while I'm here?

What are your thoughts on why the drop kick is barely used anymore?

[Baby Lee]

Originally Posted by ptlyon

What are your thoughts on why the drop kick is barely used anymore?

Flutie retired.

[BossChief]

Originally Posted by Simply Red

Do you have any Football questions while I'm here?

You seem funny.



























PS Thank you for the morning chuckle

[kepp]

I'd assume that having different sized tires when in 4wd would give you similar results as sharp turning on dry pavement when in 4wd. You know how the tires "jerk" because the two front ones are traveling different distances when the drivetrain is expecting them to travel the same distance?

[Tombstone RJ]

edit: I misread your OP, I think you will be ok IF you keep both tires on the same axel and I'd keep them on the rear axel. If you rotate them, just switch sides (hopefully they are not directional tires).

[kepp]

Originally Posted by Tombstone RJ

edit: I misread your OP, I think you will be ok IF you keep both tires on the same axel and I'd keep them on the rear axel. If you rotate them, just switch sides (hopefully they are not directional tires).

If he's in 2wd, yes. But when in 4wd the drivetrain is going to want all four tires moving the same distance per rotation.

[Tombstone RJ]

Originally Posted by kepp

If he's in 2wd, yes. But when in 4wd the drivetrain is going to want all four tires moving the same distance per rotation.

Yah, that might be a problem. That being said, I see 4WD trucks driving around with different size tires on. For example, they will have one tire with absolutely no tread on it (causing it it to spin faster) and on the other side they will have a brand new tire with tread on it, so in theory, even if they are the same size tires, one is spinning faster (or slower) than the other because of tread wear. Now, long term, this will affect the differential and turning and all that and also, the people who are doing this basically look like they don't give a crap because it's an old jeep or whatever. But yah, when the truck is in 4WD there might be issues.

[kepp]

I think the gist of it is that you'd be better off finding another two cheapo tires of the same size.

[ROYC75]

2wd, same axle, OK. Do not mix them up on rotation.

4wd, engaged, not good.