Hi Guys,
I want to get new tires for my '79 Coupe DeVille Phaeton. I think the original tire specification was G78-15 6x15.
(1) Would the correct modern equivalent be 215/75R15 or, if not, what's correct?
(2) What's the correct whitewall width?
Any advice would be greatly appreciated, thanks!
JH
215-75R-15 is the correct size. Whitewall is 1.3"
Here is a thread from earlier this summer on the subject giving several options. Hopefully most of them are still available.
https://forums.cadillaclasalle.club/index.php?topic=174440.0
Since that last thread was posted, I no longer recommend Coker American Classics. The set I bought in 2013 are still on the car and ride fine.
A new set purchased in 2021 for another car rode fine for the first three years, but this year they began causing the car to vibrate terribly at highway speed. The year before that problem surfaced, I purchased another set for another car in 2023 and that car also has the same highway speed issue of the other car. Just the Cokers bought in 2013 still ride fine. I now have eight tires that still look new with almost no wear that will have to be replaced so I'm not pleased to say the least.
SureTracs in the 215 size w/1.3" WW no longer seem to be available but keeping the whitewalls white is a major chore so they'd be out of consideration for me anyway.
I don't know whether to be astonished or infuriated that there are so few options for one of the most voluminous sized tires (ie 215/225) ever used across so many years makes and models. Especially since the era of cars they belong on (1977-1984) is one that is gaining the most in collector popularity now. Not to mention owners of later year cars who often prefer the 1.3" WW instead of 3/4" WW that GM cars began adopting in 1985.
Quote from: Eric DeVirgilis CLC# 8621 on December 15, 2024, 02:18:47 PMI no longer recommend Coker American Classics.
Eric, thanks for the info!
Are you saying you don't recommend any tire made by Coker, or just the Coker American Classics line? I ask because I see that Coker offers a 215/75R15 with the correct whitewall width as part of its "Classic Star Series." Is there a difference between "American Classics" and "Classic Star," or is it just the case that, as you see it, Coker is Coker and you're going to avoid them?
The only other new tires I see in this size are the Diamondback Auburn Premium and the Diamondback I, both of which only come with huge whitewall widths...
JH
Until now, I've never heard of the "Classic Star" line by Coker so I'm not in the position to offer any opinion on them. Just the American Classic which I chose mainly because the tread design is somewhat similar to the pattern used on OEM tires. The pattern on Diamondback radials that everybody seems to favor, I never cared for. Another car that I recently purchased had a new set of Diamondbacks already on the car and other than the tread, I have no complaints with the performance of the tires whatsoever. DBs are also more expensive than the Cokers however.
I don't know what else to advise other than this. In any case, the correct WW on a 215 for a 77-84 RWD Cadillac is 1.3" or slightly above.