Go Back   iRV2 Forums > TRAVEL TRAILER, 5th WHEEL & TRUCK CAMPER FORUMS > Trailer Towing and Tow Vehicles Discussion
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 08-13-2013, 03:57 PM   #1
Junior Member
 
RLM4x4's Avatar
 
Join Date: Mar 2013
Location: Elizabeth, IN
Posts: 24
20" or 17" tires?

I have a 2007 Ford f-250 crew cab diesel. It came factory with 17" tires but when I bought it someone has put 20" tires on it. My question is as far as towing a fifth wheel should I keep the 20's or go back to the 17's? getting ready for some new rubber and was just wondering pro and cons of the difference.
Thanks
All opinions welcome. LOL
__________________

__________________
2002 Keystone Hornet 5th Wheel
2007 Ford F-250 XLT 6.0 Diesel
RLM4x4 is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 08-13-2013, 04:05 PM   #2
Senior Member
 
Mr_D's Avatar
 
Solo Rvers Club
iRV2 No Limits Club
Join Date: May 2011
Location: Vancouver, WA
Posts: 28,535
Probably check with Ford but as I understand it the certifications for towing are made with the OEM tires and wheels. Changing to a different size without factory approval probably would not be advisable.
__________________

__________________
2009 45' Magna 630 w/Cummins ISX 650 HP/1950 Lbs Ft
Charter Good Sam Lifetime Member, FMCA, SKP
RV'ing since 1957, NRA Benefactor Life, towing '14 CR-V
Mr_D is offline   Reply With Quote
Old 08-13-2013, 04:20 PM   #3
Senior Member
 
BFlinn181's Avatar
 
Gulf Streamers Club
Join Date: Jan 2012
Location: Cincinnati
Posts: 16,263
I agree with Mr._D, height, rear end ratio, etc. all set up for the shorter tires. Larger tires will effect your towing ability and speedometer reading.
__________________

Bob & Donna
'98 Gulf Stream Sun Voyager DP being pushed by a '00 Beetle TDI
BFlinn181 is offline   Reply With Quote
Old 08-13-2013, 04:21 PM   #4
Senior Member
 
powerboatr's Avatar
 
Damon Owners Club
Freightliner Owners Club
Join Date: Mar 2006
Location: North East Texas
Posts: 3,666
you can go to fords vehicle site and check, but 17" usually carry the higher capacity than the 20" tires and wheels

not sure why....may have to do with sidewall loads or something


https://www.fleet.ford.com
__________________
USN Retired, Life time member of the DAV.
Enjoying the 2008 Damon Tuscany 4056, no your eyes are fine, there are really 6 slides
2016 Expedition Toad on Hauler flat bed
powerboatr is offline   Reply With Quote
Old 08-13-2013, 07:07 PM   #5
Senior Member
 
Join Date: Sep 2012
Posts: 4,232
I'd compare rim weight ratings. If they are the same or better and cover your rear GAWR, I'd just go with what you want. You can get a tire for either one to make them basically the same gear ratio in the end.
__________________
jesilvas is offline   Reply With Quote
Old 08-13-2013, 08:43 PM   #6
Senior Member
 
sswilson's Avatar
 
Winnebago Owners Club
Join Date: Nov 2012
Location: Cobble Hill, B.C.
Posts: 1,283
If I am correct, your 20" wheels probably have low profile tires on them and realistically are the same circumference as the old 17" wheels and standard tires. This should not affect your speedo. The 20 " are probably passenger tires rather than LT (light truck) tires which would give you better control and weight capacity. I have a F150 and I really noticed the difference when I went to oversized LT tires. I carry a heavy Goldwing in the back and don't feel the weight like I did with passenger tires. Albeit my speedo is now out but I know how much.
__________________
Steve and Sheri with Archie (and Hiro, R.I.P.)
2000 Winnebago 35U, Ford F53/6.8l V10
F150 Ford and Vintage Aspencade.
sswilson is offline   Reply With Quote
Old 08-13-2013, 09:09 PM   #7
Senior Member
 
Join Date: Apr 2004
Posts: 1,082
Ford has a 20" option for the F250 and F350 SRW for '07 model year.
The tire is a LT275/65-20" E at 3415 lbs capacity on 20" wheels rated at 3525 lbs capacity.
These 20" LTR E tires are not a 20" P tire. Apples vs oranges. You didn't give any size and load range . These tires are heavy and will have more parasitic drag over say a LT265/75- 17" E tire. Some guys like the big tires for looks or the higher load rating.

They are a upgrade in capacity however they are expensive to replace. Your call.
__________________
'03 Dodge 2500 Cummins HO 3.73 NV5600 Jacobs
'98 3500 DRW 454 4x4 4.10 crew cab
'97 Park Avanue RK 28' 2 slides
JIMNLIN is offline   Reply With Quote
Old 08-14-2013, 07:48 AM   #8
Senior Member
 
wandering1's Avatar
 
Join Date: Nov 2007
Location: NC
Posts: 450
Send a message via ICQ to wandering1
Real simple, look at the plate inside the door frame and that will tell you the size tires your truck are supposed to have.
__________________
Wandering1
wandering1 is offline   Reply With Quote
Old 08-14-2013, 08:28 AM   #9
Junior Member
 
RLM4x4's Avatar
 
Join Date: Mar 2013
Location: Elizabeth, IN
Posts: 24
Jim is correct. Whoever put the 20" on used OEM fords rims with Goodyear Wranglers. My thing is the price of the tires 20" run approximately 300-375 a tire while 17" run 140-180 a tire. If the speedometer reads 60 I'm actually doing 64. The tire experts (Big O) tell me the 20" would be better. Having problems finding a used set of OEM 17" rims
__________________
2002 Keystone Hornet 5th Wheel
2007 Ford F-250 XLT 6.0 Diesel
RLM4x4 is offline   Reply With Quote
Old 08-14-2013, 08:38 AM   #10
Senior Member
 
dlovitt's Avatar


 
Texas Boomers Club
Entegra Owners Club
Join Date: Jun 2009
Posts: 1,788
Tires 20" run approximately 300-375 a tire while 17" run 140-180 a tire. The tire experts (Big O) tell me the 20" would be better.

Which would you rather sell if you're the tire store even if markup is the same for each? And I'm pretty sure the markup % is at least as much on the 20's as the 17's-probably more.
__________________
2018 Newmar Dutch Star 4369, Spartan K2 Chassis,
Cummins ISL 450HP, Allison 3000

2015 F-150 King Ranch LB 3.5 L twin turbo Ecoboost Toad, Texas Boomers RV Club
FMCA F292298, NRA Benefactor Life Member
dlovitt is offline   Reply With Quote
Old 08-14-2013, 08:54 AM   #11
Junior Member
 
RLM4x4's Avatar
 
Join Date: Mar 2013
Location: Elizabeth, IN
Posts: 24
I agree. That's why I'm really considering going back to 17" tires . Just having trouble finding some OEM rims
__________________
2002 Keystone Hornet 5th Wheel
2007 Ford F-250 XLT 6.0 Diesel
RLM4x4 is offline   Reply With Quote
Old 08-14-2013, 10:07 PM   #12
Senior Member
 
dlovitt's Avatar


 
Texas Boomers Club
Entegra Owners Club
Join Date: Jun 2009
Posts: 1,788
Quote:
Originally Posted by RLM4x4 View Post
I agree. That's why I'm really considering going back to 17" tires . Just having trouble finding some OEM rims
Salvage yard? Can you find original owner? They are probably in the back of his garage.
__________________
2018 Newmar Dutch Star 4369, Spartan K2 Chassis,
Cummins ISL 450HP, Allison 3000

2015 F-150 King Ranch LB 3.5 L twin turbo Ecoboost Toad, Texas Boomers RV Club
FMCA F292298, NRA Benefactor Life Member
dlovitt is offline   Reply With Quote
Old 08-14-2013, 10:22 PM   #13
Senior Member
 
Winnebago Owners Club
iRV2 No Limits Club
Join Date: Apr 2010
Posts: 713
Haven't talked about gear ratio so here goes if the circumference of the 20's is greater you will have higher gear ration with less pulling power. Usually a ratio in the 4's has more pulling capabilities than one with a lower number, say in the high 3's. I just reread what I wrote and now I am confused as well.

Don G.
__________________
Grimesy is offline   Reply With Quote
Old 08-14-2013, 10:47 PM   #14
Senior Member
 
Join Date: Sep 2012
Posts: 4,232
Makes sense: larger tire, lower gear ratio number, less wheel power.
Smaller tire, high gear ratio number, more wheel power.
__________________

__________________
jesilvas is offline   Reply With Quote
Reply

Tags
tires



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 03:36 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.