1996 Dodge Grand Caravan LE-Tires

It's quite obvious, I would think. Replace all four tires with P215/65's.

It isn't obvious at all. Two of the tires are almost new. If it isn't unsafe to use them why would I throw $200 away to replace them? My original question. i.e., "Would it be unsafe to use P215/65 size tires on the front, and P215/60 on the rear?", remains unanswered. What are you, an auto repair snob?

Little Jimmy Olsen, taking no crap from Linux users . .

Why don't you just answer the intent of the original question and explain why you feel that it is not acceptable to have mismatched tire sizes. If you mistmatch on the same axle I could see it being a bigger potential problem that matching on the same axle but different front and back...? I for one don't know enough to know why it would or would not be safe, but a "because I said so" answer tells us nothing except that you seem to enjoy giving folks crap for questioning your great knowledge.

Wesley

I did. He asked what he should do, and I explained what he should do.

Where did I say anything like "because I said so"? Go back and look, and you'll see that I did NOT give anyone any crap, until AFTER he gave some crap in response to my answer. Get on his ass, not mine.

You did "say" it was OK, by giving me shit for answering the question with an answer you didn't want to hear. As for more explanations, here's a couple: Unsafe cornering and speedometer inaccuracies. There are probably more reasons.

What? You are the one who cannot comprehend my simple answer.

Perhaps. I'll make a point to stay out of the "Ignorant Questions" and "Stupid Car Tricks" newsgroups, so you won't get the chance.

Why? Because I correctly answered your question?

Subsequently, I

Replace ALL four.

1- Proper size from the factory. 2- Different sizes F/R WILL screw up ABS and Traction controls (if equipped). 3- Speedometer will read improper depending on how far from programmed size a tire is.

The answer to your question is no. It could lead to braking problems and cause problems with the vans computer. You need to replace all 4 tires with the correct tire size.

Here is a link that will show you the difference in the two tire sizes. Do a comparison.

Sarge

Thanks to everyone for your help.

LJO

No problem. It's interesting that you didn't get all offended by the other two people who told you the same thing I did. How come?

You replied to him in an arrogant and unhelpful manner...the other 2 were polite and gave informative answers that helped us all learn something. Gee...I wonder...

Below is my original reply to him. You actually think that is "arrogant and unhelpful"?

"It's quite obvious, I would think. Replace all four tires with P215/65's."

Come on. It's the correct advice, and we all know it. Nothing arrogant or unhelpful in there.

That's the only way he knows how to reply, just read some of the replies in here. I stopped awhile ago because of his ignorance.. Honestly I think there should be some way to keep people out of here unless they are at least 12 years old.

Glenn Beasley Chrysler Tech

Question: Why would four tires of the same size -- any size within reason -- cause problems with ABS?

It is my impression that various trim levels of this vehicle (all with ABS) are delivered with different rim diameters, widths, and tire sizes and profiles.

ldenn2 wrote:

No takers on this?

RWM wrote:

"RWM" wrote: "No takers on this? Question: Why would four tires of the same size -- any size within reason -- cause problems with ABS? It is my impression that various trim levels of this vehicle (all with ABS) are delivered with different rim diameters, widths, and tire sizes and profiles."

On cars and trucks that have antilock brakes (ABS), most vehicle manufacturers say replacement tires should be the same size as the originals. This is necessary because the diameter of the tire affects how the wheel speed sensors read, which in turn affect the operation of the ABS (and traction control) system. Changing to a larger or smaller diameter tire, or installing different sized tires front and rear can upset the operation of the ABS system. This may create braking problems and/or cause the ABS warning light to come on (which means the system is deactivated). You can drive the vehicle this way as you still have normal braking.

Sarge

Thanks.

I can easily understand the issue of a mismatched size within the four rolling tires, though even there, the simple action of differential wheel speed on inside and outside tires of the same size, rounding a corner results in a small difference, but a different size all the way around would not trigger the sort of speed sensor differential that triggers the ABS or TCS functions.

Especially since, as far as I recall, this platform has been delivered with a variety of wheels diameters, widths and tire sizes/profiles.

RWM wrote: "Thanks. I can easily understand the issue of a mismatched size within the four rolling tires, though even there, the simple action of differential wheel speed on inside and outside tires of the same size, rounding a corner results in a small difference, but a different size all the way around would not trigger the sort of speed sensor differential that triggers the ABS or TCS functions. Especially since, as far as I recall, this platform has been delivered with a variety of wheels diameters, widths and tire sizes/profiles."

In simple terms, ABS uses the wheel sensors which determine speed to determine when ABS is needed and when to release it. Number of rotations will be higher or lower then depending on whether you increase or decrease OEM tire sizes.

Sarge

That is understood, but if all tires are the same size -- any size within reason -- rotations will be the same.