question for you factory 20" wheel owners

[redbandit98]

My truck came stock with 17s. I just installed factory 20s with 275/65/20s. Does the trucks that came with the factory 20s have a 20" spare or is it a bigger tire in a 17" size? I would assume it would be the same size as the wheels that came on the truck but you know how manufacturers like to cut corners. Im only asking because I am wanting to get a matching spare. If they came with a 20" spare, I may just go to the scrapyard and see if I can find one. If they came with a 17" spare, Ill just keep my wheel and see if I can find a tire shop to swap me tire sizes.

thanks
matt

[smokeum99ta]

Not sure if my spare is a 17 or 18 but I know that mine didnt come with a 20" spare for sure

[TOPFUELF250]

You got me wondering so I went and checked. 275/70/18. It's been hanging under the truck since I bought the truck new.

[44magnum]

Well my truck didn't come with a spare so I got a 17" rim and a used 285/75-17 which was as close to the height of the 275/60-20's that are on my truck. It dosn't matter what size rim you use as long as the tire as the same height.

[redbandit98]

Thanks for the feedback. Yes, I know it does not matter what size wheel. I was just thinking if it did come with a 17" spare with a bigger tire (for the 20s) I may could go to the scrapyard and swap my spare for the right size spare (wheel and all) and not have to mess with taking my tire off and finding the right size etc.

[Tempsho]

Originally Posted by TOPFUELF250

You got me wondering so I went and checked. 275/70/18. It's been hanging under the truck since I bought the truck new.

On paper:

spare tire 275/70R18 = 33.1"

The factory tire on the 20" wheel 275/65R20 = 34.07"

44magnum, your 285/75R17 = 33.8"

Looks like that might be the closest size tire to match a the factory 20" rubber.

I am about to pick up a set of factory 8 spoke 20" wheels and factory size rubber for my Excursion, and I was wondering the same thing about the spare tire.

265/75R16 = 31.6"

So it looks like i'll have to run a different spare tire. I wonder how big of a tire I can fit in the factory space inside the back of the Excursion.

[dc.snowball]

redbandit98...i got an 11---350 w/ 20".. went to rotate tires.... and ....spare is same size but a different brand. dealer said it is UNUSUAL for the spare to be same brand. ford sez to x tires not rotate with 5. the axle tires and the spare are from diff. sources and is pure luck if spare is a match. this is probably the 1st truck ever owned, ford-dodge-chevy, that the spare is diff. although the rim is diff. too....guess they feel that the spare(with basic rim) is a temp fix only.

[redbandit98]

i could care less what brand or even what size the wheel was as long as it was the same diameter. Too bad its not. I dont see why in the heck they couldnt put the same diameter tire under there. I guess it wont fit, or I guess its close enough that they are comfortable enough to run it on the back with the limited slip diff. They have to be ok with running the different size tire on the back becuase 90 percent of truck owners arent toting around another jack or jackstand. Without one of these swapping wheels would be a pita. (jack front up remove front wheel, put spare on, go to back jack back up put front wheel on back). Thats not too bad in your garage but on the side of a interstate half in the ditch, I think you wouldnt want to be playing nascar jack-man swapping wheels around.

[fifty]

There are two different diameter spares out there. When I went to factory 20's I was at a dismantler and was lucky enough to be able to compare. They were about an inch difference in overall diameter.

[44magnum]

Originally Posted by redbandit98

i could care less what brand or even what size the wheel was as long as it was the same diameter. Too bad its not. I dont see why in the heck they couldnt put the same diameter tire under there. I guess it wont fit, or I guess its close enough that they are comfortable enough to run it on the back with the limited slip diff. They have to be ok with running the different size tire on the back becuase 90 percent of truck owners arent toting around another jack or jackstand. Without one of these swapping wheels would be a pita. (jack front up remove front wheel, put spare on, go to back jack back up put front wheel on back). Thats not too bad in your garage but on the side of a interstate half in the ditch, I think you wouldnt want to be playing nascar jack-man swapping wheels around.

Thats what I do if I have failure on the back. I also always have an electric impact in my truck at all time to make this sort of thing go quicker.