Tire Size Question - Page 4

jage · 01-07-2009, 06:01 PM

It does make sense, they use the F-series SuperDuty axle and change the back spacing to match with spacers would be my guess. A lot less expensive than manufacturing the axle parts to change the SuperDuty axles to 8/6.5

adventureduo · 01-07-2009, 09:45 PM

Quote:

Originally Posted by jage

It does make sense, they use the F-series SuperDuty axle and change the back spacing to match with spacers would be my guess. A lot less expensive than manufacturing the axle parts to change the SuperDuty axles to 8/6.5

So you're saying they put a stock Super Duty axle upfront and then leave the rear the stock E350 d60 and use a spacer to 8x170mm in the rear?

jage · 01-08-2009, 12:05 AM

That would be my first guess. Or the 09 E series has SuperDuty rear axle, making it all 8/170. I believe I heard in 08 the 8 on 6.5 front axles became no longer available which is why Quigley had the fire sale, but it might be that the vans went to SuperDuty patterns.

We need to get some Quigley people on these forums to answer this stuff!

adventureduo · 01-08-2009, 09:57 AM

Interesting. Does that mean Surfgeeks SMB is 8 on 170mm also? Surfgeek?

Steve_382 · 01-17-2009, 05:19 PM

I'm not sure what they do on the rear axle either. When I get home from Florida, I'll try to check the parts list for some clues. It does use the 8x170 pattern for sure. That caused much confusion when I bought the new wheels and tires as the dealer couldn't believe they were 17" either. I wasn't able to find a wheel I liked that had zero backspacing either (that's what Ford recommends for the F350) and went with 40 mm (1.5") spacing wheels. I think this contributes to the tires rubbing the plastic trim under the factory chrome bumpers in sharp turns. SMB trims the plastic on their conversions, but I haven't done mine yet.

jage · 01-22-2009, 06:13 PM

Quote:

Originally Posted by Rockman

Ive got 285/70 17 on my Quigley and they rub really really bad. They look like they have plenty of room when straight, but I "think" that the American Racing Baja wheels are offset or something (they were put on by previous owner) and maybe they swing out when turned.

Anyone know how I can tell if they are offset? I really dont want to buy new rims (unless someone on here wants them), and I really dont want to downsize the height of the tire.

Anyone have any suggestions on "testing" to see if the rims I have need to go?

BTW, awesome tire coverage on this tread.

Rockman · 01-22-2009, 06:58 PM

Thanks for that Jage,

just for future searches
American Racing Baja with 3 inches to front rim ( 6 inch backspacing) and im guessing a 10" wide rim.

So this leads me to think that my wheels "stick out" .5 in further than yours, and your is fine...
I will look tomorrow and see if I think that .5 in would make a lot of difference. Im just not sure.

Anyway, thanks a lot for the info

Switchfoot · 01-22-2009, 08:34 PM

I was told all Quigleys prior to 2005 had the 8x6.5 bolt pattern. In 2005 Ford switched to a coil spring front axle for the 4x4 F-250/350 and Excursion and switched to the 8x170 bolt pattern. Quigley buys Ford factory axles and transfer cases for their conversions and had to install rear spacers/adapters to be able to use one type of wheel on the vehicle after 2005. In 2007, the front brakes were redesigned by Ford (larger rotors), which required the use of larger 17" rims to clear the calipers.

Rockman - sounds like you have your rims have too much backspacing if your 285s are rubbing while turning. Your tire needs to be further away from the chassis = less backspacing. You should be able to run those tires just fine. More backspacing pulls the tires in and is easier on the hubs and bearings; but if you can't run the size tires you what, is it worth it?

I'm running 315/70-17s and they don't rub while turning at all. My rims are Helo Guns (a bit blingy yes) 17"x9", 6 mm offset and 5.25" backspacing.

Also, you don't have to live with an inaccurate speedo if you don't want to. I contacted Heber at SMB and he emailed me the "cheat codes" to trick the van PCM computer so my speedo now reads dead on with 315s verified by GPS. The van computer doesn't have a wide range of tire size inputs so you end up playing with the tire size and rear axle ratio to make it "right". Cost me $100 at the Villa Ford to reprogram the computer.

adventureduo · 01-22-2009, 09:08 PM

Villa Ford did it? Shoot im right down the street from you. Swing by sometime.

geoffff · 01-23-2009, 12:21 AM

Quote:

Originally Posted by Switchfoot

Also, you don't have to live with an inaccurate speedo if you don't want to. I contacted Heber at SMB and he emailed me the "cheat codes" to trick the van PCM computer so my speedo now reads dead on with 315s verified by GPS. The van computer doesn't have a wide range of tire size inputs so you end up playing with the tire size and rear axle ratio to make it "right". Cost me $100 at the Villa Ford to reprogram the computer.

Oh! I would love to get my hands on those speedo-calibration cheat codes! Could you share the technique with me?

I've been trying to use a "Predator" programmer to eliminate the 94 MPH top speed limiter from my van, but the Predator screws up the Sportsmobile's speedo calibration. (And, no, the Predator's built-in speedo calibration functionality doesn't work.)