Forum Home Forum Home > CJ-2A Discussion Area > General Discussion
  New Posts New Posts RSS Feed - Tires, How low can they go?
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Tires, How low can they go?

 Post Reply Post Reply Page  12>
Author
Message Reverse Sort Order
jaksjep View Drop Down
Member
Member
Avatar

Joined: 03 Nov. 2013
Location: Southern CA
Status: Offline
Points: 471
Post Options Post Options   Thanks (0) Thanks(0)   Quote jaksjep Quote  Post ReplyReply Direct Link To This Post Topic: Tires, How low can they go?
    Posted: 03 Mar. 2016 at 6:41am
Contact the tire manufacturer and see what they say???
My posts are my personal opinion and are not legal advice as I am not an attorney. If you act on any of my comments you do so at your own risk.
Back to Top
jpet View Drop Down
Moderator Group
Moderator Group
Avatar
Sponsor Member x 5

Joined: 30 Apr. 2008
Location: Ramsey, IL
Status: Offline
Points: 11173
Post Options Post Options   Thanks (0) Thanks(0)   Quote jpet Quote  Post ReplyReply Direct Link To This Post Posted: 02 Mar. 2016 at 1:25pm
Originally posted by Joe Friday Joe Friday wrote:

Jeff- go ahead and run 8 but watch your footprint. Bias tires "oil can" and you will lose traction because the centerline lifts. ..... 
 I'm guessing the smart thing to do would be to chalk up the tire and check the perpendicular contact, keep airing down till the center starts to disappear?
CJ2A #29110 "General Willys"
MB #204827 "BAM BAM"

"We do what we can, and we try what we can't"
Back to Top
willys54wagon View Drop Down
Member
Member
Avatar

Joined: 24 July 2008
Location: Ames, IA
Status: Offline
Points: 1444
Post Options Post Options   Thanks (0) Thanks(0)   Quote willys54wagon Quote  Post ReplyReply Direct Link To This Post Posted: 02 Mar. 2016 at 1:17pm
If you read through the pictures here you will see dash instructions of 7 lbs for entering and leaving water, but you knew that from past experience?  I would assume the military had done some research on low tire pressure.
 
http://www.ebay.com/itm/131739208219?rmvSB=true


Edited by willys54wagon - 02 Mar. 2016 at 1:28pm
Two jeeps on the road, one is close and the rest are dreams.
Back to Top
Joe Friday View Drop Down
Moderator Group
Moderator Group

Sponsor Member x 2

Joined: 26 Dec. 2010
Location: Jeep Central
Status: Offline
Points: 3633
Post Options Post Options   Thanks (0) Thanks(0)   Quote Joe Friday Quote  Post ReplyReply Direct Link To This Post Posted: 02 Mar. 2016 at 2:13am
Jeff- go ahead and run 8 but watch your footprint. Bias tires "oil can" and you will lose traction because the centerline lifts. also, for Moab you don't want to lose axle clearance by airing down too much. It makes the steps harder and you loose grip on side slopes.
I've done 'tire test hill' at 35 psi in 2wd. there is a ton of hype out there.
Back to Top
jpet View Drop Down
Moderator Group
Moderator Group
Avatar
Sponsor Member x 5

Joined: 30 Apr. 2008
Location: Ramsey, IL
Status: Offline
Points: 11173
Post Options Post Options   Thanks (0) Thanks(0)   Quote jpet Quote  Post ReplyReply Direct Link To This Post Posted: 02 Mar. 2016 at 1:22am
Thanks for the input guys. I know there are lots of variables what I am looking for is testimony from someone who has actually tore up a tube because they aired down too low ..... other than a flat

..... or testimony from those who have aired down tubes below 10 lbs with success.

Edited by jpet - 02 Mar. 2016 at 1:25am
CJ2A #29110 "General Willys"
MB #204827 "BAM BAM"

"We do what we can, and we try what we can't"
Back to Top
Mark W. View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 09 Nov. 2014
Location: Silverton, OR
Status: Offline
Points: 7923
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mark W. Quote  Post ReplyReply Direct Link To This Post Posted: 01 Mar. 2016 at 11:50pm
Keep in mind a stock running sad Willys Jeep will climb a hill if it keeps traction steep enough to flip one over. SO if you have no roll bar/cage you best be careful.
Chug A Lug
1948 2A Body Customized
1949 3A W/S
1957 CJ5 Frame Modified
Late 50's 134L 9.25"clutch T90A D18 (1.25") D44/30 flanged E-Locker D25 5.38 Since 1962
Back to Top
Mike S View Drop Down
Member
Member


Joined: 20 May 2006
Location: West Coast
Status: Offline
Points: 2318
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike S Quote  Post ReplyReply Direct Link To This Post Posted: 01 Mar. 2016 at 10:53pm
A lot depends on the weight of your vehicle, type of tires, and the surface you are driving on. I have aired down the tires of my F350 crew cab 1 ton to 14-15 psi when launching a 4500 lb. boat on a dual axle trailer across the beach in Baja. These tires are Toyo M55s 285-75-R16 load range E.

If you are driving a very lightweight vehicle (like our Jeeps) I expect that you could go to 10 psi - maybe a little less. The more plies in the sidewall, the more lateral support you get, the lower you can air down. The best index might be the percentage increase of the tread width. Going from 6" tread width to 7.5" is probably realistic - try this in your driveway and and see how much you need to air down to get to that width. 
'47 CJ2A -- #114542
Warn FF D41 rear
Lock-Right locker
11" drum brakes
Dual master cylinder
T90C Transmission
16 X 6 Jeep truck wheels
Cooper STT Pro tires
Back to Top
jpet View Drop Down
Moderator Group
Moderator Group
Avatar
Sponsor Member x 5

Joined: 30 Apr. 2008
Location: Ramsey, IL
Status: Offline
Points: 11173
Post Options Post Options   Thanks (0) Thanks(0)   Quote jpet Quote  Post ReplyReply Direct Link To This Post Posted: 01 Mar. 2016 at 7:46pm
Originally posted by rocnroll rocnroll wrote:

I would go 8 to 10.....
 I'd like to run 8.  I figure if the valve stem slipped gradually, you could just keep an eye on it and if it starts to slip, flip your tires from side to side to cause the action to go the other way.  I'm just wondering if anyone has run 8 with a tube and actually spun one that ruined the tube.
CJ2A #29110 "General Willys"
MB #204827 "BAM BAM"

"We do what we can, and we try what we can't"
Back to Top
rocnroll View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 20 July 2005
Location: Tuscumbia, AL
Status: Offline
Points: 13563
Post Options Post Options   Thanks (0) Thanks(0)   Quote rocnroll Quote  Post ReplyReply Direct Link To This Post Posted: 01 Mar. 2016 at 7:41pm
I would go 8 to 10.....but like stated above opinions will vary.

Never spun a valve stem out of a tube (but that is all based on 4 cylinders)



'47 CJ2A PU
'48 CJ2A Lefty

"Common sense is not that common"
Back to Top
jpet View Drop Down
Moderator Group
Moderator Group
Avatar
Sponsor Member x 5

Joined: 30 Apr. 2008
Location: Ramsey, IL
Status: Offline
Points: 11173
Post Options Post Options   Thanks (0) Thanks(0)   Quote jpet Quote  Post ReplyReply Direct Link To This Post Posted: 01 Mar. 2016 at 7:32pm
BTT

My question is, has anyone actually spun a tire or ripped a valve stem because they aired down too much?  If so, how low did you air down to? I'm talking tubes of course.

It just seems to me that 15 psi is not low enough to gain significant traction.
CJ2A #29110 "General Willys"
MB #204827 "BAM BAM"

"We do what we can, and we try what we can't"
Back to Top
Joe Friday View Drop Down
Moderator Group
Moderator Group

Sponsor Member x 2

Joined: 26 Dec. 2010
Location: Jeep Central
Status: Offline
Points: 3633
Post Options Post Options   Thanks (0) Thanks(0)   Quote Joe Friday Quote  Post ReplyReply Direct Link To This Post Posted: 13 Feb. 2014 at 4:40am
Ditto on what Carl said, 15-20 psi.
 
Your wheels probably don't have safety humps in the bead area.
 
Regardless of whther the tires are 4 or 6 ply rated they are likely 2 ply Nylon.
 
I've dome most of the Moab trails in a stock 3B including tire test hill and lionsback, buy did not do challenges like Mickey's hot tub or the escalator due to probable body damage.
Back to Top
Carlsjeep View Drop Down
Member
Member
Avatar

Joined: 15 Jan. 2011
Location: Taylorsville Ky
Status: Offline
Points: 2642
Post Options Post Options   Thanks (0) Thanks(0)   Quote Carlsjeep Quote  Post ReplyReply Direct Link To This Post Posted: 13 Feb. 2014 at 2:32am
Stan, you may be surprised at just what your stock Jeep will do. Use 15 to 20 psi and it would help to have a Lock Right in the rear axle. But that won't happen this trip unless it's already in it.

BobW told me some of the 16" rims have a lip like the tubeless rims do and they hold the tire on better. 

When climbing, the approach you take to the hill and rock is most important. 
Life is only as good as you make it.
Back to Top
jeeper50 View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 01 Mar. 2008
Location: Spanish Fort AL
Status: Offline
Points: 2579
Post Options Post Options   Thanks (0) Thanks(0)   Quote jeeper50 Quote  Post ReplyReply Direct Link To This Post Posted: 12 Feb. 2014 at 9:12pm
i run mine offroad and around town at 15lbs.

Belleview ol skool winch soon.
'48 CJ2A 283 V8 sm 420 granny low, tera low D18, overdrive,lockers

Texan at heart,Alabama by retirement

Back to Top
Metcalf View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 21 May 2009
Location: Durango, Co
Status: Offline
Points: 736
Post Options Post Options   Thanks (0) Thanks(0)   Quote Metcalf Quote  Post ReplyReply Direct Link To This Post Posted: 12 Feb. 2014 at 6:51pm
Cool! I have wanted to head down that way. I am driving over to the Rubicon trail this June so I might just have to stop in that area and poke around. 

Wheeling is wheeling. I spent a lot of my youth in a bone stock flat fender getting into just as much trouble as I do now! You'll have a blast. 


42 MB that had a one night stand with a much younger 69 CJ5 and a 50s GM truck.



Back to Top
smfulle View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 16 Sep. 2010
Location: Ogden, Utah
Status: Offline
Points: 6123
Post Options Post Options   Thanks (0) Thanks(0)   Quote smfulle Quote  Post ReplyReply Direct Link To This Post Posted: 12 Feb. 2014 at 6:43pm
Metcalf, we're actually going to SouthWEST Utah, St George area. Lot of family there so free lodging. Same red rocks though not quite so famous as Moab.
 
Don't think I'll take on things in my stock rig that you do in your flat fender on steroids rig, especially since I am really a novice driver.
I'm really pumped about this trip. Doesn't compare to your adventure to the snow fields, but this will be my first time on anything other than dirt and mud.
 
Here's a video from the trail we are going on. It's not a flat fender and I won't be trying this obstacle, but you can see there is some challenging spots there.
Stan
48 CJ2A (Grampa's Jeep)
59 Chevy 1/2 ton
Grampa's Jeep Build Thread
Back to Top
Metcalf View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 21 May 2009
Location: Durango, Co
Status: Offline
Points: 736
Post Options Post Options   Thanks (0) Thanks(0)   Quote Metcalf Quote  Post ReplyReply Direct Link To This Post Posted: 12 Feb. 2014 at 6:18pm
Moab in a flat fender is a BLAST! 

The tubes kinda complicate things, but on 15 and 16" rims the bead lip is still the same as a tubeless tire correct? The only thing to really watch out for is spinning the tires in the rim. You don't really see that happen too often at 10psi and above. 5-10psi I have seen it happen on new rims with smooth bead lips, espeically chrome steel rims. 

If your still running manual steering you probably don't want to go much below 10psi. I would start at 15psi and go towards 10psi as you feel more comfortable with it. 

If you can, you might grab a spare tube to take with you. I would imagine that shops in town might have one....but it could come in handy out on the trail too worst case. 

I wish I could get over there this weekend! 

This thread needs a picture of a flat fender in moab.....


Have fun, stay safe. 
42 MB that had a one night stand with a much younger 69 CJ5 and a 50s GM truck.



Back to Top
smfulle View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 16 Sep. 2010
Location: Ogden, Utah
Status: Offline
Points: 6123
Post Options Post Options   Thanks (0) Thanks(0)   Quote smfulle Quote  Post ReplyReply Direct Link To This Post Posted: 12 Feb. 2014 at 6:07pm
Well, neither Coker or Summit Racing, from whom I bought the tires give an actual ply rating other than "bias ply". I suppose it might say something on the tire itself, but I don't remember. I'll check it this evening.
Stan
48 CJ2A (Grampa's Jeep)
59 Chevy 1/2 ton
Grampa's Jeep Build Thread
Back to Top
F Bill View Drop Down
Member
Member

Sponsor Member x 2

Joined: 05 Dec. 2005
Location: central Texas
Status: Offline
Points: 7752
Post Options Post Options   Thanks (0) Thanks(0)   Quote F Bill Quote  Post ReplyReply Direct Link To This Post Posted: 12 Feb. 2014 at 5:45pm
How many ply rating are those Cokers?
If you haven't checked out the tech FAQ section, go to:
http://www.thecj2apage.com/forums/tech-faq_forum57.html
for a lot of great stuff you need to know!!

Back to Top
 Post Reply Post Reply Page  12>

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.06
Copyright ©2001-2022 Web Wiz Ltd.