Question Hi Barry, I hope you can help, I recently purchased a 1995 chevy G20 conv. van...it has the original tires on it, it only has 67,000 miles. the tires need replacing and they are an odd size 255/60/R15..the original tires are Goodyear eagle GTII..on Aluminum 15 inch eagle rims..Id like to replace the rims as well, they are a pain, and I think one of them is warped or bent ( which I hear is a problem with aluminum rims)..Do I have to stay with the same size tire..I'm OK with the 15inch rim but do I have to keep the 255/60 R15's..a mechanic told me that I HAD TOO..that the tires size is geared to the weight distribution in a conv. van..I just don't want to pay out a BIG CHUNK of $ for that odd size tire and it seems the only company that makes it is Cooper Cobra..HELP, any suggestions are welcome. Thankyou, Patti
AnswerPatti,
First let's do the basics:
On every vehicle sold in the US - and I understand this is a worldwide practice as well - there is a sticker – commonly called the vehicle tire placard - that lists the original tire size and the proper pressure for that size. The placard is usually located on a doorpost or in the glove box – but sometimes it is located in the trunk or on the fuel filler door.
BTW, it doesn't matter who makes the tire or what pressure is listed on the tire's sidewall, if the tire size is the same as the placard, then the pressure listed on placard is also appropriate.
According to Tire Guides, a 1995 Chevy G20 came in a variety of configurations and a variety of tires, but none of them was P255/60R15. I suspect that the original factory tires were taken off and a more appealing set of tires and wheels were applied by the converter - which was common in that era.
Keeping in mind that this vehicle is from the era BEFORE the Ford / Firestone situation, I am looking at this with a great deal of skepticism. Not only were vehicle manufacturers doing some things that weren't exactly the best for tire durability, but the conversion companies were (and still are) largely unregulated. It's not that there aren't regulations, it's that they just aren't enforced. The bottomline is that conversion vans from that era could use tires with larger load carrying capacities. So let's do that.
(What this means is that your mechanic's comment of keeping the same tire size is just not right for this situation. Normally, he would be correct, it's just there is more to it because of the age of the van.)
There are 2 limiting factors: How much room is there under the fenders, and how wide the rim is. I think we can assume that since GM specified up to a P235/75R15 for this vehicle, that there is plenty of vertical room - and since the conversion company put on 255/60R15's, there is plenty of width. That helps a lot.
But the rim width could be a problem since we do not know what it is. Before you make the final purchase decision, you need to see what those rims are. The width will be on the back of the wheel. It will likely be 8". So for now let's assume that it is.
I did a quick check on Tire Rack to see what was available in a 255/60R15 - and there were 3 tires - a Goodyear, a Firestone, and a BFG. They all were priced just under $100 each. Not a bad price.
With that in mind, I priced a much larger (and therefore, safer) size of P235/75R15 - which will fit on an 8" rim, and they were in the mid $70's. That's a bit cheaper, but you are going to lose the meaty look of the wider tire.
I'm going to recommend a 255/70R15 - and Tire Rack lists 8 tires. Not only is this as wide as the current tires, but it has more load carrying capacity and is priced in the same range as the 255/60R15's.
This might throw the speedometer off, but I am sure you can compensate, But remember you have to check the width of the rim.
