Stock tire size....

[RaccoonJoe]

As the title says...this is a thread about stock tire sizes!!. I'm curious to know what the stock tire size is for my '89 XJ Limited. The option/build sheet I got from the dealer last month says that it came with 225/75R16 tires, but it also says that it came with 16 inch chrome wheels. I'm rolling on the standard 15 inch, gold spoked, ugly-as-hell alloy Limited wheels.....with 235/75R15 Bridgestones.

The owner's manual lists everything from a 195/75R15 up to 225/70R15, and the sticker inside the glovebox lists 220/70R15. What to believe?!?!


Trying to calculate actual mileage vs. odometer mileage....for accurate MPG figures and so I get paid correctly!!
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[KarlVP]

Go with what the build sheet says. Rim size matters not.

And with tires in those size ranges, you aren't going to be off by more than a tenth of a mile.

Going from 28 inch tires to 33's put me at a loss of 2 tents of a mile per.

 

[RaccoonJoe]

I understand that I'm looking at *maybe* 2-5% loss on the odometer....but I would like to have it as accurate as possible.

You say to go with the build sheet....My problem there is that I'm *obviously* running 15 inch rims, when the build sheet says 16's. Not a huge deal, but I know that the build codes changed when Chrysler re-did everything......which makes me question the truth in the build sheet.

 

[Kyle Petterson]

I've never heard of an '89 coming with factory 16's.

 

[ren]

The factory tire size on my '88 Limited was the 225/70/15. So says the glove box lid, AND the ORIGINAL full size, matching spare.

 

[PhotographerMike]

A couple of things.

All of the "original" tire sizes are very close to the same diameter, so the rolling distance would be the same.
If you have a GPS check your actual speed versus the indicated speed. My tires "grow" with speed, at an indicated 35 mph I'm going 32 BUT at an indicated 85 (closed course, professional driver) the speedo. is right on.
If you drive slow would you get paid for driving more miles?

Also; Chrysler has been known to recycle code numbers. My '89 build sheet says "ERB - 3.XL Mid V6 Engine". I checked the back seat, it's missing! All I have is a straight 6 in front.

 

[RaccoonJoe]

A couple of things.

All of the "original" tire sizes are very close to the same diameter, so the rolling distance would be the same.
If you have a GPS check your actual speed versus the indicated speed. My tires "grow" with speed, at an indicated 35 mph I'm going 32 BUT at an indicated 85 (closed course, professional driver) the speedo. is right on.
If you drive slow would you get paid for driving more miles?

Also; Chrysler has been known to recycle code numbers. My '89 build sheet says "ERB - 3.XL Mid V6 Engine". I checked the back seat, it's missing! All I have is a straight 6 in front.

I have had this same discussion with several folks in the past, dealing with my S-10. I went from a stock 205/75R15 to a 235/75R15, ran the numbers through the formulas, and figured that my odometer/speedo were 6.5% off. Nobody believed me, so I clocked it on 2 GPS systems (and a buddy on the local PD force). Turned out I was right.

Just trying to do the same thing here....



And no, I don't get paid more if I drive slower. Hell, if that was true I'd be running around on 13" wheels, racking up 2x the correct mileage!! :twak:

 

[xraze]

My ride is an '89 laredo purchased new. Tires from the dealer were P215/75r15's. Michelin x/c tire that I wish they still made. I had over 50,000 on them and they came off. Currently still on a buddy's utility trailer. I'm sure there were various factory sizes offered. xraze

 

[thall]

xraze comment

X2...

my 90 laredo purchased new also with 215/75-15 Michelin X/C.... agree right at 50k on them... then i put 245/70-15 on it before trading it off in 93.

and i changed the speedometer gear... think 2 teeth.... but don't remember.