Directional tire installed on rim backwards

[y_p_w]

Originally Posted By: wrcsixeight
I remember reading that back in the day radial tires should not have their direction of travel reversed. I was wondering if newer directional radials get messed up in a similar fashion.

This is on a c-5 corvette rear tire with continental contitrac dws, installed within the last 3 months, and was just noticed it was installed backward. Not sure of mileage on tire.

What's a Contitrac DWS? Contitrac is their SUV line.

If it's the ExtremeContact DWS, then those are non-directional asymmetric. They simply say OUTSIDE on the outside edge but can be mounted in either direction. As long as they're mounted properly with the OUTSIDE label against the outside of the rim, they could theoretically go in either direction.

My 2004 WRX manual says to keep the tires on the same side when rotating. My '95 Integra GS-R recommended fronts straight to the back, and rears crossing over to the opposite front. They had alternate recommendations for directional tires. The factory tires were non-directional, and the first pair of tires I bought were Pirelli P6000s, which were non-directional and had a tread design that looked the same in either direction. I'm surprised it's still on the market after 17 years. After that I only got directional tires.

I'm not sure how many vehicles still come with recommendations for crossing the tires back to front.

 

[CapriRacer]

Some background:

In the early days of steel belted radial tires - we are talking the 1970's here - every tire manufacturer (including Michelin) had trouble with belt leaving belt separations. One of the phenomenon's noted was the failures started around the steel belt wires and mostly on one side of the wire - and it was thought that reversing the direction of rotation aggravated the situation.

As a result, the recommendation was to NOT cross rotate (which had been the standard) - but to rotate on the same side.

Please note: The forces involved in accelerating and braking are opposing, but for some reason, these forces were not considered important enough to over-ride the recommendation.

Eventually, it was found that there was a chemical used as part of the bonding of rubber to steel that degraded into an acid in the presence of water - and when it was replaced with something that didn't do that, the bonding problem pretty much disappeared.

Firestone was the last one to discover this and they suffered because of it. Remember the Firestone 500? That was replaced by the "721"? Yes, it was THAT situation.

Nowadays, tires don't have that problem and cross rotation is encouraged by the tire manufacturers.

- BUT -

Many vehicle manufacturers haven't updated their owners manuals from those days. It seems odd, but I know they don't go through them very often - usually just to update certain portions that actually do need changing. And even then, that happens only half the time. A good example is AWD's and having 4 identical tires. There are some owner's manuals need ta warning, but don't have one.

So don't be surprised if your owners manual has only a "same side" tire rotation recommendation - and don't think something terribly will happen if you cross rotate. The important rotation is the front to rear part, and the side to side part is just an added plus.

 

[Jarlaxle]

I ran into that recently at a tire shop. Simplest way to make the point: radials cave been recapped for something like 30 years...and there is a 50% chance that any capped tire will be reversed!