I bought this old pickup a year ago and it had P235/75R-15 tires on it. I never thought much about it until I was going to put tires on it. I looked at the door panel and the existing tires are quite a bit larger than what the manufacturer suggests. I think it's 195's it calls for on the door tag.
My question is: what are you guys running on your pickups?
Speedo is off of course. I'm thinking about putting the original size back on.

Gus

On my 76 D100 I am running....235-75-15s! Light truck tires, though, not passenger car tires. If you are driving a truck or van you need to use light truck ("LT") tires that have stiffer sidewalls. This avoids overheating the tire and having a blowout.

The door stick recommends a 195 what? What is the aspect ratio?

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Casually looking for a Clifford hyperpak intake for cheap.

Dang, I'll have to look at my trucks. I don't think I have ever run 195s on any of them. I have 31-10.50 X 15 on my 4X4 and I just got an 89 D150 that looks like it has 235s on it.

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-MattMan
LEANED & MEAN

Ijust looked on the door post. P195/75 - 15

Is that a Chrysler stickert or some other sticker? Even Tire Rack says the tire size is 225/70-15. You should never use a "P" tire (passenger car) on a truck.

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Casually looking for a Clifford hyperpak intake for cheap.

We have had quite a few 80-87 trucks and I think most of them had 235/75 on them. One did have 225 /75. Not at all sure what they called for, but I'll go look on my door post later.

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Info on why you should only use light trick tires on a truck instead of the passenger car rated tires: http://www.tirerack.com/tires/tiretech/ ... techid=195

Not trying to start anything, just trying to keep you safe.

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Casually looking for a Clifford hyperpak intake for cheap.

With all due respect Reed I really don't think I need saving anyway. I DO always appreciate your input though.
I had no intention of putting passenger car tires on this pickup. I use it to pull my sawmill around and haul an occasional log or two if they aren't too big. So LT's are the only way to go.
You asked what size tires it called for so I put `er on the site. I did, in fact, get the info. off the Mopar sticker on the door jam.

I can only speculate as to why this PU calls for the tire size it does. it is only a light 1/2 ton 2WD but it is very odd that a full sized PU would call for that tire size. That is the same size my 1995 Mercedes diesel car takes.

I'll take a picture of the sticker. Not sure how to get it on the site but I'll figure something out.

I still would like some of you to look at the sticker on the door of your PU to see what size it calls for (80's light 1/2 ton 2WD's with /6's) to see what it says. Mine can't be the only one.

My 85 D100 2WD door sticker calls for P195/75 on the front and rear. Can't imagine how small they would be!

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

OK Rick, thanks, for verifying my sanity.

Sorry Reed, I just read my original post. I see I put. "P" in front of the 235. This PU does have LT's on it. I was so shocked to see P's listed on the door panel; that's what I wrote.

I put new treads on old blue. I went to a 215/75R15 (195's weren't even available). I like the results. They don't look that much shorter than the 235 but are narrower; which I like.

Pickup handles itself much better in the hills. much less shifting down for the small hills we have around here.
It also starts a roll easier from a dead stop. After a few hundred miles I doubt I'll ever go back to 235's. I think the smaller tire is both easier on the clutch and the motor.
That's just me.
BTW I did a 250 mile trip with this old girl a few weeks ago and broke 20 mpg! was close to 21!!

Changing the tire size will artificially change the rear ratio... when you went from LT235/75/15 to a LT215/75/15 you reduced the outer diameter of the tire about an inch... if your truck is equipped with 3.55 rear gears, your speedometer gear in the transmission will be off a tooth or more...

The smaller engine will like the nicer rear ratio given the vehicle but your mph and mpg are now going to be off which will throw off your calc a bit...

It is not lost on me what changing tire size does to ones speedo or odometer. Besides, that mileage was logged with the 235's still on the pickup. I'm assuming with the 215's on everything will be more accurate; as its closer to the original size tire.

If you go back to the beginning of this thread you will see that the manufacturer called for P195/75R-15 as an original equipment tire size. In fact, with the 235's on the speedo was off around 7mph; according to GPS measurements. Hence, I'm thinking that the 215's would be a more normal size for this pickup than the 235's that were on it when I bought it. And yes, mpg estimates were bound to be off but not sure how much. I'm not enough of a math weenie to want to figure it out.
I just thought it interesting how much different the pickup handles with a shorter, narrower tire on it.