The Conservative Cave

Interests => Around the House & In the Garage => Topic started by: DLR Pyro on March 10, 2015, 04:25:54 PM

Title: Ford F-150 - question about upgrading wheels from 17" to 20"
Post by: DLR Pyro on March 10, 2015, 04:25:54 PM
Last month I bought a new Ford F-150 truck.  It came with 17" wheels but because Ford enlarged the wheelwells for the truck bed, the 17" wheels look puny and out of place.  I didn't give it much thought but my wife said it looks funny.  I have found several ads listing stock Ford 20" wheels on craigslist (usually brand new and from people who are upgrading to custom wheels). 

My question is do I need to get a new speedometer gear or have the dealer do anything to the computer module to compensate for the larger wheel diameter the 20" will give me?
Title: Re: Ford F-150 - question about upgrading wheels from 17" to 20"
Post by: Chris_ on March 10, 2015, 04:41:16 PM
If you're able to retain the same diameter with the new wheels and tires, you shouldn't need to make any changes.  Anything else, and I'd be asking the dealer if you're working with them.
Title: Re: Ford F-150 - question about upgrading wheels from 17" to 20"
Post by: Big Dog on March 10, 2015, 04:48:29 PM
Last month I bought a new Ford F-150 truck.  It came with 17" wheels but because Ford enlarged the wheelwells for the truck bed, the 17" wheels look puny and out of place.  I didn't give it much thought but my wife said it looks funny.  I have found several ads listing stock Ford 20" wheels on craigslist (usually brand new and from people who are upgrading to custom wheels). 

My question is do I need to get a new speedometer gear or have the dealer do anything to the computer module to compensate for the larger wheel diameter the 20" will give me?

One percenter! Occupy DLR Pyro's driveway!
Title: Re: Ford F-150 - question about upgrading wheels from 17" to 20"
Post by: JohnnyReb on March 10, 2015, 05:53:01 PM
Damn computers make changing wheel and tire sizes a nightmare now days. Ask some trust worthy person.....like a hot rodder.
Title: Re: Ford F-150 - question about upgrading wheels from 17" to 20"
Post by: ExGeeEye on March 10, 2015, 06:19:59 PM
If you consider that an "upgrade"...
Title: Re: Ford F-150 - question about upgrading wheels from 17" to 20"
Post by: Bad Dog on March 10, 2015, 06:26:11 PM
If you're able to retain the same diameter with the new wheels and tires, you shouldn't need to make any changes.  Anything else, and I'd be asking the dealer if you're working with them.

Chris is right but, I seriously doubt you could get tires for 20" rims that would be the same diameter as those on the 17" rims.  You should be able to simply switch out the little gear in the transmission that drives the signal generator for both the computer and the spedo.  You might search Ford truck forums for the formula to determine the proper gear or a dealer service rep. might be able to help you.  I went through the same thing on my car when I changed both tire diameter and my ring and pinion set.