My great Ambulance Tire debate

[Amboater]

Hey gang, this is my very first post so apologies in advance for all the tribal norms I'm sure to violate

I recently picked up a 2003 E-350 Turbo Quigley Ambo with only 106k miles on it. I've dedicated the last month of my life to scrapping off all the decals, and will be soon turning to the tires to beef it up. Amazingly, despite the emergency squad putting a Quigley conversion on this thing back in the day, they left the tires at the stock 225/ 75 size which kinda look like skateboard wheels on it. The tires are brand new so I'm feeling inclined to do the upgrade right away while I can resell these things as mint. I have narrow it down to pretty much two options I'm debating between. Note that presently I have about a 12" gap over the front tire to the fender and maybe 5-6" on the rear.

Option A: 235/ 85/ 16

This is the size my local tire shop said was the max they recommended without having to modify anything else on the vehicle. He priced out a set of Wildpeaks for me that were super cheap as well. At 31.7", these wouldn't be nearly as beefy as some of the monster truck Ambo setups around this club, but they're 2.4" higher than my current skateboard wheels so would definitely be an improvement

Option B: 255/ 85/ 16

This is the size I would love to put on for esthetic purposes if I could simply wave a magic wand. Would involve lifting the rear up more and possibly a few other changes that are above my paygrade. They're nearly 4" taller than my current tires so it would be a substantial change. Only tires I can find in this size are Discoverer S/T's which are $100 more each than the Wildpeaks.

Given that I'm no handy Andy mechanic like a lot of you folks are, I'm leaning towards the much cheaper and simpler Option A so I don't get myself in over my head right out of the gate. Could always upgrade to Option B in year 2 or 3 when I have more knowledge and experience under my belt. Would love to get some additional viewpoints though. The vehicle is going to be used for cross country kayak trips and will be on pavement 99% of the time except for the occasional fire road or snow storm. Generally the goal is to make the Ambo look as cool as possible, while sacrificing as little drivability as possible.

I look forward to your feedback!

 

[zelseman]

We are in a Chevy short bus and will be going to 235/85/16 shortly. 255’s are a good size but they are hard to find especially when abroad.

 

[Westsidetroopy]

Sweet ambo, lucky find. The 235/85r16s will be the easiest option for sure, cheaper, much easier to find and sound like they would suite your needs. The 255s do look great and from what I’ve read (correct me if I’m wrong) are the largest tire one can run duallies with without using wheel spacers. If you did need to lift your rig to clear the 255s it wouldn’t be much at all, likely a 2” lift which on that vehicle wouldn’t be terribly expensive to have a shop instal (as far as suspension lift prices go in general). The BFGoodrich Mud terrain km 2 & 3 as well as the Yokohama Goelander mud terrains are also available in 255/85r16 (if you’re ok with mud terrain tires), prices are roughly similar to the Cooper Discoverers. I have a similar rig to yours and plan on going with the 255s partially for looks, but mostly so I can easily handle rough dirt roads and get to the more remote camp sites with ease.

 

[Len.Barron]

I have wildpeaks on my rig and love them...I resisted going from 33 to 35 in (it was tough to let that go) but the wheel wells on my van really don't support the extra diameter when you start stuffing/turning. Also you need to consider the extra load on steering (particularly when not moving or at low speed) a 4x4 rig with a heavy front axle weight and big tires is hell on a steering box, I just added hydro assist to mine and still need to get my hydroboost unit high-flowed..

 

[cjken]

You may be able to get away with the 255’s (option B) with out additional lift just minor fender trimming.

I singled mine which made sense since I put a narrower box on it.
My rear is not lifted beyond stock Quigley height and I’m running 35 12.5 r17 size tires
I actually had 37’s at one point, but had to tear up my front fenders to fit those. Now that I have the smaller tires I’m considering getting the weldtech or advanced fiberglass front fenders to replace my hack job.

 

[cjken]

Also, I would resist lifting the front of the stock Quigley. I believe that it is asking for potential death wobble issues due to changes in suspension geometry.
In addition, raising the CG has no benefit. I say trim fenders if you have to.
The 35’s and 4:10 gearing is just about perfect in my opinion.
Option b would probably put you in a better RPM range on long hwy runs (assuming you have 4:10 gearing.
I believe ambulances are geared for quicker acceleration for short runs around town rather than hwy cursing. I guess that factor really depends on your intended usage.

 

[Amboater]

Thank you all for your great feedback! Ultimately the path of least resistance won out in my mind, and I just couldn't pass up on getting a set of 6 Wildpeaks for $121 each! Going with Option A. I can get crazy with the monster truck look later down the road when I know slightly more what I'm doing

 

[FDM2012]

Also, I would resist lifting the front of the stock Quigley. I believe that it is asking for potential death wobble issues due to changes in suspension geometry.
In addition, raising the CG has no benefit. I say trim fenders if you have to.
The 35’s and 4:10 gearing is just about perfect in my opinion.
Option b would probably put you in a better RPM range on long hwy runs (assuming you have 4:10 gearing.
I believe ambulances are geared for quicker acceleration for short runs around town rather than hwy cursing. I guess that factor really depends on your intended usage.

Hey Ken, Hope you have been well.

I did the Agile 4x4 RIP Kit with my 36 x 15 Mickey's, and have had ZERO wobble.
It's probably a lot more than Amboater would want to do himself, but a good shop in his area may do it for a fair price.

And I did SuperSprings in the rear to correct the sag and I gained an inch or so, as well. They are adjustable, and I am in the lowest setting. So I have room to play for the rare occasion that I might tow with it. #NoRegrets

Just my $.02

 

[Amboater]

Nice snorkel Eric! I bet that comes in handy during hurricane season down there . Definitely gonna give Super Springs a try so thanks for the tip on them

 

[cjken]

I agree Eric
I actually have the rip kit as well.
I was not really considering that to be a lift, but I guess it raises it a bit.
I’m curious about your front fenders. I guess I’ll check out your thread. I way over cut mine for 37’s. May try to re do this spring.

 

[Amboater]

Here's the results gang! 235/ 85 Wildpeaks with Supersprings and blacked out the stock steelies. Its looking night and day different now from when I first bought it. Thanks for all the feedback and help to get me to this stage. On to the next phase...

 

[cjken]

Looks great!! Definitely a solid choice!!
16” rims? My understanding is that you can air down 16’s but not 16.5’s.

 

[Amboater]

Looks great!! Definitely a solid choice!!
16” rims? My understanding is that you can air down 16’s but not 16.5’s.

Thanks! Yeah, they're stock 16" wheels. I was nervous the 235/ 85's wouldn't look beefy enough on them, but they look great! Definitely an AT look while sacrificing as little functionality as possible, which was the goal. Next up is to strip that chrome brush guard down and black it out as well

 

[1000arms]

Thanks! Yeah, they're stock 16" wheels. I was nervous the 235/ 85's wouldn't look beefy enough on them, but they look great! Definitely an AT look while sacrificing as little functionality as possible, which was the goal. Next up is to strip that chrome brush guard down and black it out as well

You have fresh rubber for now, but when you need to replace your tires, you might look at
BFGOODRICH® Commercial T/A® Traction. They are stud-able, and although available in only a few sizes, 235/85R16 E is available.