It has taken awhile, but finally located a set of clean alloys from an '11 Ranger. After mounting a used 215/65-15 on one to check clearances, this size will fit fine. The new 15X7 wheels protrude outward 1/2" compared to original wheels which were 215/70-14 size. I am quite sure the 215/65-15 will give a noticeable improvement in handling. The original 14s made the van handle like a boat, with too much lean and roll. The shorter sidewall of the 65 series will hopefully tame that down. But.....would the 215/70-15 be just as good in that regard? Reason I ask is, I believe there is ample space in the wheel wells to fit the larger size. Had the new wheels protruded a full inch outward, maybe not, but only 1/2" I'm guessing will be okay. Going to the 215/70-15 should also make the speedometer accurate once again. The old 215/70-14 made the speedo read 63mph when radar and gps readings indicate 60. Being off 3mph is fine I guess, but I'd rather have it within 1 mph.

 

The stock tire size is 215/75/14, which is about an inch taller than 215/70/14. But 215/65/15 is only slightly taller than that, so it's not going to change your speedometer readings much. The 215/70/15 is closer to stock height.

The lower profile tire will have a stiffer sidewall for better stability, and if it actually has more tread, it will also have more traction. So overall handling, such as it is with a minivan, should improve.

I will also note that the manufacturer specs show that the taller profile tires have higher load ratings. So for the tires I bought for my 15" wheels, the 215/70 size has 100 lbs greater load than the 215/65. Something to keep in mind if you're going to haul heavy loads.

 

Thanks for responding. Before doing the trial with 215/65-15, I had checked various sources as to specs, and found what you are pointing out in respect to sidewall stiffness and handling. The tag located on the Aerostar door jamb lists two tire sizes, 215/75-14 and 215/70-14. As there was no explanation for why both sizes are listed, I assumed that perhaps the smaller size 215/70-14 was listed for AWD models due to the extra horsepower consumed by the added mechanicals. I thought it unlikely Ford would list two sizes had they not a particular reason in mind. If limited availability of the larger size, 215/75-14, was an issue, it is doubtful they would have chosen it as an option at all. But, perhaps it was used on older AWD Aerostar as the OEM tire. Mine is a 1997, and from what I have found on various forums, 215/70-14 was the tire Ford used on AWD models that year. I did not find where 2WD versions in 1997 used the 215/75-14 size. But, perhaps it was.

Back to the original question, would using the larger 215/70-15 tires instead of the smaller 215/65-15 offer the same improvement in overall handling and driveability? Or would the larger size be a step back toward the same handling and driveability of the original size 14" tires? If not, the other advantages of the 215/70-15, those of increased load capacity, more accurate speedometer readings, and a tad more ground clearance could outweigh any disadvantages such as slower acceleration. OTOH, if the 215/70-15 has the potential to rub on the inside fenderwell should the suspension bottom out when hitting a pothole or speed bump, that might be a disqualifier for using the 70 series tire.

I'm open to both sizes, but if the 215/70-15 has no significant disadvantages, I will likely go that way.

 

Yes it will, and I give this size out if ever asked my opinion for general purpose grand touring. But it will be for naught if shocks and bushings aren't there. A similar tightening comes from sway bar swap/installs.

The larger diameter of the /70 would give better mileage, traction and handle deeper snow. As pointed, it will also get you a higher load, but it may be irrelevant because you'll be bumpstop'in against weak springs beforehand. And if the wheel offset is too much outboard, the additional /70 height may additionally limit the load.

I found the speedo to match roadside radar signs and GPS. But note that as tire thread wears, the speedo will creep upward slightly for the same actual/fixed speed traveled. Or considered the other way, the actual speed will creep downward for the same indicated speed.

Fyi, I've used 215/70-14, 215/65-15, 215/60-15 (by mistake), 225/55-17, and I'm currently on 225/60-16. Depending on rim offsets, some are chain friendly, some not.

 

Thanks for jumping in on this with added info. My plan is to install inflatable air lifts inside the rear coils to help when hauling heavy loads or towing a front-heavy trailer. When you had the 215/70-15 tires on your Aero, did you notice much loss in engine torque, particularly in the 50-70mph range?

Not sure how much your rims protruded outward, but as mentioned mine protrude 1/2" to outside more than original 215/70-14 wheels/tires did. Realizing that 215/70-15 would add nearly another 1" diameter more than 215/65-15, I have some concern that this may be enough to cause collision between tire and inside of fender well when/if the springs were to bottom out over rough road conditions. Is this what you encountered with the 215/70-15?

 

Daryl, I have been running 215/70r15 tires for the past 4+ years with no issue of bottoming out or rubbing on turns, even with old springs. Before that I ran 215/65R15 tires, which gave a more aggressive look, but just did not seem to be able to hold the weight I haul sometimes and started to "weathercheck" after a couple years.


The 70s series does give you more of a truck bounce, but I believe it is because of the higher load range.

 

Thanks 93nighthawk for adding your experiences with the 215/70-15 tires on your Aerostar. Are you running 15X7 wheels, too? How much outward offset do your wheels have in comparison to the original 14X6 wheels that came on the Aero?

Do you find the 215/70-15 tires to have similar handling characteristics as the smaller 215/65-15, by not having the rolling, bouncy, bubbly feel of the 215-70-14 tire?

 

I got some Explorer 15x7 wheels with the tear-drop holes, and I think almost all of the added width ended up being outward. I chose those because from what I saw, any inward shift would have brought the tire too close to the brake hose. So the 215/65/15 tires I got looked like they would hit the inside fender lip in some combination of turn and bounce limit. I therefore folded in the inner lip as a precaution against tire scrape, even though others who have done this conversion assured me that I should have had no problems.

I believe all the AWD vans came with 3.73:1 rear end, which may help compensate for the heavy weight of the additional drivetrain parts. So I'm not sure if they needed the shorter tires for that. But I also remember that the AWD vans had 1" more ground clearance than the RWD vans, per factory specs. So that may be from a combination of taller tires and stiffer springs.

In any case, and this may be obvious, make sure you get the same size for all the tires in an AWD van, and rotate them before the wear on either end gets too severe, or they can fool the AWD computer and it will try to lock the front and rear at the wrong times.

I really doubt you will feel much of a difference in acceleration between these sizes, as they're all going to be slug slow. I had a RWD extended van with a 4 liter engine and I think a 3.25:1 rear axle, and its acceleration was quite obviously faster than the AWD. The only difference between the two were the AWD parts, and the rear axle ratio, which was less advantaged on the 2WD, and it still beat the AWD. They were 1990 and 1991 models, so I doubt there was much difference between the engines.

 

I have been running Explorer slicer rims which are 15x7. There are pics somewhere around here of my gal wearing them.


They don't really have a bubbly feel, but rolling/bouncing tends to be an issue when not weighted down, but I am also running MOOG cargo springs in the back w/ Monroe load adjusting struts, which push the rear end up quite a ways when empty.

 

Not anywhere close to the bouncy, wallowy, tippy behavior of the original 215/70-15, correct? By "truck bounce", I'm interpreting as firmer and quicker response. Is this close?

 

Yes, I would call it more of a "truck bounce" instead of a "car like ride."


But I use my van for more than hauling the family, This past summer I hauled several 1200lb loads of cement, 4x8 sheets, 2x4x10's, plus multiple other chore stuff. That 8' bed is nice to have when needed.

 

Thanks for clarifying. Most of the time, I haul anywhere from 3 to 6 people around, but occasionally haul up to 1000 lbs of cargo internally, plus pull a 1500 lb. trailer with tongue weight of 150 lbs. The 65 series tires would probably be fine, since the occasional heavier hauls are maybe twice a month at most.

My main reason for going with 15" wheels is to get away from the feeling I'm piloting a little boat on top of some big swells, constantly needing to make more than normal corrections while steering, not to mention the extremely limited selection of 14" tires. The existing shocks seem okay, but the tires have the weak sidewalls which I suspect are responsible for the majority of it.

If the 70 series give the same feel as the 65 series, i.e. firmer, less wallowy ride, while at the same time giviing quicker, more responsive steering, the advantages of the 70 series should outweigh the disadvantages. Next step is to find a used 215/70-15 and try it on the vehicle to check how it fits inside the wheel wells. As I haven't found anyone else using these exact wheels on their Aero, the offset and backspace measurements may or may not be issues. Best to simply try one on for fit...

 

While you are in there checking so closely, headzup on the axle being off center, causing different clearances Left v Right.

Also, taking my current setup as an example, there can be different issues front v back. I have scrubbing in back when loaded and travel dips at highway speeds. In front, even unloaded, I can scrub when I'm steering off center (thus tire crosses the fender lip) while braking hard combined with corner G's. So, you shouldn't just mount, stare and conclude.

 

Thanks. Good suggestions that I will be sure to follow. You are currently running 225 width tires now and have the problems with tires rubbing from time to time. Did you have the same issues with the 215 width?

 

Never a prob with 215/65's with a (early Explorer) wheel offset of ~12mm.

Don't know my Lincoln Town Car offset but they are likely in the 6mm range. Definitely further out than what you are showing in your pics. Strange that I don't have that measured and calc'd precisely. Then the 225's add another 5mm.