14.00R20 Super Singles to 11.00R20 duals

[nlauffer]

OK, I have searched for this and have found plenty information on going from duals to singles. I am wanting to take a 923A1 back to duals. This is due to a height restriction which a few inches would benefit considerably. I can buy 12.00/20's in nondirectional for $150 brand new. The original size I believe is 11.00/20. So two questions.

1. Will the 12.00s work fine as duals?

2. Do I have to do anything other than just take the singles off and install the duals?

I know the duals take an extra budd lug, and that the wheels need to be installed with the correct facement. Inner wheel out and outer wheel in. Also the 12.00s will have their own rims.

thanks in advance for the help.

 

[Karl kostman]

I am not 100% positive on the fit of the 1200s but you will have to do nothing to the truck other than take the singles off and install the new tires in the dual configuration, the budd lugs are of course necessary to do this but nothing needs to be done to the truck other than that! Sorry I could not be so sure about the size of the tires!
KK

 

[nlauffer]

Thanks for the quick reply. I would assume the 12.00s would fit the same rim as 11.00s without incident.

 

[patracy]

I know Ron (73m819) has 12.00's on his M819. The main concern with duals is that the sidewalls do not touch each other. So you should be fine with that.

BTW, if you need thimbles and nuts, I'm working on converting my 931 to a 931A1 and will have them left over soon.

 

[Sephirothq]

Are those tires radial or Biased ply? I know the 900 series really need to have a radial tire on them with the ABS system.

If you were closer to PA I would swap you a set of 11.00 x 20 for your tires if they were in good condition.

 

[juanprado]

To make your speedo read correctly, You would need to remove the adapter that the A1 & A2 have due to the bigger tire. I don't think a 12 will make much diff instead of 11 as they are close in height but from a 14 it should.

You should be able to sell it in the classifieds as many are looking for it when stepping up.

 

[nlauffer]

Thanks for the replies. I didn't think about the 12.00s being radial or bias. They are a bias tire and wouldn't be good with the ABS. So I will narrow it down to locating the 11.00R20 Goodyear G177. I did find some close, but they only have 5 rims w/tires.

The speedo is something else I didn't think about. Although, this is for a fire truck and won't see much highway time.

Also, in reference to this being a fire truck. This truck will see some decent sand, as I am in the western edge of South Central KS. By no means as much as other places, but how well do the duals hold up in the sand. The dueces I currently have do alright. The big benefit of the 4 trucks I got was the super singles for the sand. Just one needs to be a little shorter. Maybe I can leave the singles on and chop the cab.

 

[MWMULES]

North East of you 2 hours is BFR in Salina and Glen 91W350 has stacks of g177 Radials and ndcc 11x20 already mounted on 923 rims

 

[DeucesWild11]

Are you planning on putting the 12's all around or just on the back for the duals? Reason I ask is that I was thinking of duals on the back and singles on the front but wanted the front wheels wider. However, then I wind up with wheels in the back just slightly shorter in hight than the front, if put into 4x4 (bobbed) I think I would run into problems with the different sizes.

 

[nlauffer]

DeucesWild11,
I believe you would run into some interesting problems with that. The front and rear diffs would be turning at different speeds, but the trans case woud be trying to turn at same speed. Something has to win and I bet the diffs would. There goes an expensive trans case. Although, what you are referring to has been done on a GMC C70 in my area, but it only moves when there is ice. No problem as the wheels will slip. I bet it still won't hold up as long.

 

[nlauffer]

MWMULES,
I will be driving right through there to pick up my next two 5 tons on Monday. I have never been there, but will be stopping on the way back. I hope Glen doesn't mind the permanent smile that I'm sure to have.

 

[steamshovelman]

Wire brushed and painted a set of eleven standard military rims and stamped right on them was max. tire size 12.00-20 and that was what i was running with no problems at all. (grin) Also absolutely NO PROBLEM running bias tires (full set) all around with ABS, if you read the military literature you will find that they are not prohibited, the radials are desired. The ABS will help the shortcomings of bias non directional tires on paved roads, especially when they are wet or slippery. I run stock 11:00-20 NDCC tires on my M818 and have never had any problems but drive like it's an accident waiting to happen when it gets wet or icy. Even with an awesome set of radials i would drive the same unless Iit was a matter of life and death! My tires thump for a few miles in the morning too and really rattle your teeth sometimes until they get warmed up. If i could afford it i would have all the different tires to suit the mission. NDCC's for military shows so it's stock, 11:00R20's for heavy hauling with my lowboy and the 14's for off road for sure. If i could only have one set of sneakers 12.00R20 Michelin XML's would do!

 

[nlauffer]

I still haven't decided if it is an absolute need for duals. I did stop by BFR in Salina and spoke with Glen (91W350) on my way back from picking up the two new 923A1s. I would say if you are in the area it is a must that you stop by. It's just like a giant playground for adults. I did find plenty of those G177s. I also found a couple hardtops I will probably get to replace the softtops I have on the two new ones.

 

[steamshovelman]

For an off road fire truck super singles like you already have fit the projected use best. For all the reasons Uncle Sam put them there you want them too! Rocks and mud don't get trapped like they do with duals, better traction, a little more ground clearance, better flotation on the front axle and if they have run flats and bead locks you have some of the safest sneakers available purpose built to take on rocks, creeks, mud, snow and?! ....fire lol, small arms fire that is and keep on going for miles to safety!

 

[chrsbb19]

I can buy 12.00/20's in nondirectional for $150 brand new. The original size I believe is 11.00/20. So two questions.

Me Wanty... I have 11x20, set now. was wanting to do super singles but didnt do the research. Im moving to cali in oct, afre you willing to swap or can i get the info for new tires either 11x20's or super singles.