Decision Time - Single Rear Tires vs Dual on Ambulance

billiebob

Well-known member
That's cool. Bolt on floatation!

Reminds me of these.
View attachment 694464

Reminds me of the Michelin TRX plus 1 metric tires. I think they only came of Fords early 1980s. I had an Escort with them. It was a blast to drive, hotter than Lee Iacoccas GLH but stupid expensive. Come new tire time I bought 4 rims ans 4 13" tires.... for less than the cost of 1 Michelin TRX Metric thing.

340 and 390 rather than 14 and 15
13.385" and 15.35" they still make them for the exotics... like Ferrari in a 415 size 16.338"....

TRX-design-1024x720.jpg
 

billiebob

Well-known member
and that reminded me of this massive hail storm I drove through a couple years back. Definitely a win for skinny duallys. Anyone with fat tires was either driving at 10kph, pulled over or was in the ditch. I barely noticed it. lol

yep, 4 years ago I went from 33x10.50s ro 7.50R16s... absolutely love them.
Tall and super skinny they go thru "standing water" like an old 10 speed bicycle tire.
But cost per mile is the seller. 100K KMs vs 75K KMs per tire.
And I gained 5mpg from 17mpg to 22mpg. I always needed gas in Canmore before, Now I make it to to Calgary. 95 more miles per tank..... for overlanding that means I can leave the Jerry Can at home. Not to mention the gas savings. AND I lost no performance...... actually in bad weather they out perform the old LT 33/10.50R16s. I cannot imagine the white knuckle experience of driving thru slush on 33/12.50R16s. It is incredible how many QuadCab Pickups with monster tires I pass in a snowstorm.

I even cut down the flares to better fit the skinny tires.

DSCN2900.jpeg

So when you think super singles, understand the rear singles will track great but the front tires will now want to float. You completely destroyed the balance and you will lose steering control while the rear tires so overloaded by comparison track straight, cutting thru the slush and puddles. I've talked to guys with super singles and yeah, this is a common comment. Being uncomfortable in snow and slush and slowing down.
 
Last edited:

Bikersmurf

Expedition Leader
My observation is that empty pickups suck in the snow. Back in ‘96 we got 3’ of snow overnight. No one at the hotel, where I picked up some friends, believed I drove there. They’d watched, for over an hour, a large group of guys (10-12) try to get a new Chevy pickup out of the parking lot behind them. Meanwhile, I’d been driving through it for hours on 31x10.50 Michelin XC AT tires with 35k miles on them (less than 40% left

That said, it was the one instance where wider tires out perform tall skinnies. In many areas, the snow was 3-4’ deep on the road. Floatation was the only option. There’s no way tall skinnies could dig down to find traction.
 

Abitibi

Explorer
On mine I kept the dual axle as it is larger than the SRW axle and run single wheels on it. I do have a 2" spacer to push the wheel out. It's more for look and I'm considering taking it out as it will track better in line with the front.

My tires are rated at close to 3700lbs, same for rims so I'm good there.

Some rims offer dual wheel pattern (170 & 6.5) which comes handy!

With duallies you'll be limited with tire size. And I'm not a fan of duallies in the snow.

My ambo is 11,000lbs and feels very planted on curvy roads, no issues there.

So I'd fix your rear locker and keep that axle. Mount single 35's and if you're not happy you could always go back but I doubt you will. Plus, converting the front to dually style won't be that fun, keep it SRW :)





Sent from my SM-G973W using Tapatalk
 

iggi

Ian
Thanks David!

I went bed, confident that I was going to keep the duallies and then you come along and confuse things again. (joking)

I've been reading so much that it slipped my mind you still have your original rear axle. Thanks for reminding me.
The big decision at this point was whether I should swap that rear axle and it seems that regardless of tire/rim choice I can keep the original Dana 70 and not worry about it.
Plenty of time to sort out tires/rims later. :)

What rims and tires are you running?

Cheers,
Ian

PS Thanks for the feedback everyone. Appreciate all the perspectives.



On mine I kept the dual axle as it is larger than the SRW axle and run single wheels on it. I do have a 2" spacer to push the wheel out. It's more for look and I'm considering taking it out as it will track better in line with the front.

My tires are rated at close to 3700lbs, same for rims so I'm good there.

Some rims offer dual wheel pattern (170 & 6.5) which comes handy!

With duallies you'll be limited with tire size. And I'm not a fan of duallies in the snow.

My ambo is 11,000lbs and feels very planted on curvy roads, no issues there.

So I'd fix your rear locker and keep that axle. Mount single 35's and if you're not happy you could always go back but I doubt you will. Plus, converting the front to dually style won't be that fun, keep it SRW :)





Sent from my SM-G973W using Tapatalk
 

joeblack5

Active member
When we decided on our bus we wanted something relatively nimble.. a srw Econoline bus has 6ft03" width inside, enough for us to sleep in width wise.

The bus outfitted with 4x4, solar , tanks, tools and 4 people, two dogs comes in at 9800lbs.. for that reason I went to 19.5" wheels .
Depending where you plan to go,.... overall width can be important.
 

Attachments

  • IMG_20211030_085840309.jpg
    IMG_20211030_085840309.jpg
    3.3 MB · Views: 32

geoffff

Observer
The "rock stuck between the duals" would be a great topic for Myth Busters. But given every logging truck, gravel truck, mining truck uses dual..... often on 5 or more axles.... without an issue..... I say this is a myth.

Well, I have four times adventured with friends who roll with duallies -- and one of those times I ended up having to pull a rock out from between their duallies with my tow strap. (It was a 10-tire Deuce ½ with old military tires.)
 

billiebob

Well-known member
Well, I have four times adventured with friends who roll with duallies -- and one of those times I ended up having to pull a rock out from between their duallies with my tow strap. (It was a 10-tire Deuce ½ with old military tires.)
see we agree, a good topic for myth busters
 

iggi

Ian
Hah, you dredged up on old memory. Had a neighbor when I was kid with a an old deuce and a half and yep.. he did manage to lodge a rock between those old military duallys. They did seem very effective at rock capture, perhaps part of a secret military defence plan? ;)


Well, I have four times adventured with friends who roll with duallies -- and one of those times I ended up having to pull a rock out from between their duallies with my tow strap. (It was a 10-tire Deuce ½ with old military tires.)
 
One incontrovertible advantage of singles is the ability to deflate to 25-33% of road pressure. Certain single wheels can also accommodate internal beadlocks.
If you don’t need this and considering how much this sort of stuff costs…
 
Took this video a few years ago.

This is his 4th run, the other 3 runs he made it to the light standard before spinning out and backing up onto the ferry landing wedge. You can see him almost spin out going past the light post but..... 4th time is a charm.

Tripe lockers, 4 sets of chains on the duals. 130K pounds, 460HP. 18 speeds.... I don't miss it at all.
Many reasons to love duals.... ever seen a semi blow a tire..... and keep going.

oh yeah, for the first 30 seconds...... imagine what is going thru his mind

Good advertisement for diff locks
 

iggi

Ian
Absolutely. For a rig that sees heavy offroad use there wouldn't be much debate. It's more this combo of lots of highway miles along with deep snow parking lots and kinda rough fire road terrain that has made it a tougher decision for me.

One incontrovertible advantage of singles is the ability to deflate to 25-33% of road pressure. Certain single wheels can also accommodate internal beadlocks.
If you don’t need this and considering how much this sort of stuff costs…
 

Forum statistics

Threads
185,527
Messages
2,875,540
Members
224,922
Latest member
Randy Towles
Top