Continental MPT 80's again

[Doin_It]

So I've been taking to David Horton at firematic.com about a fire supression skid unit to mount on one of our F550's. One of the things they also do there at Firematic is tire/wheel conversions. Check his site for examples.

One conversion is the Michelin 19.5 XDE2 SRW on 19.5" wheels, the other is the MPT 80's 12.5 R20's on a 20" wheel. They are both reversible wheels (steel) that line up front to back on the truck. They have not been changing the gear ratio's on the trucks and he says in 10 years they have had no axle problems either. I'm sure these are not trucks that are always driven with the utmost of care, as I'm sure many are driven as if they were stolen.

The price for 5 tires and wheels are $6500 for the 19.5 and $7500 for the MPT 80's. The 80's require a 5" lift kit to fit right.

Sounds like I may be getting some big rubber with my skid unit.

 

[boblynch]

Thanks for the info. Does the price quoted include the 5" lift kit? Also, does it include shipping? Finally, do the wheels require any spacers or adapters or do they fit the standard bolt pattern?

Bob

 

[haven]

Here's the Firematic BRAT, a firefighters' brush truck built on
an F550 with optional 20 inch Continental MPT tires and 5 inch
suspension lift

More information here
http://www.firematic.com/trucksused/550demo_08/index.htm

I'm a bit doubtful that no gearing change is necessary when you move to a tire that is five inches taller than stock!
Stock tire for the F550 is 225/70R19.5, with diameter 31.9 inches.
The Continental MPT 81 in size 275/80R20 has a diameter of 37 inches.
The MPT 81 335/80R20 measures 41.1 inches in diameter.

Chip Haven

 

[Doin_It]

The prices quoted are just for the tires and wheels. No freight or lift kit. The 19.5's are a 2 different wheels, they aren't revesible, 2 for front 2 to back, though they do line up/track perfectly. The MPT's are reversible front to back, though the tracking is off by a 1/4" He says they haven't had issues, gearing was something I asked him about. Loaded F550 with fire skid and water, 400 gallons, the truck weighs 16,000lbs. There is a difference he says but they have no priblem driving up an down gullies and hills. Customers are happy with the truck as it is. F550's are geared lower any way, I should walk out and have a look see what I've got in mine. Other then that, I'd like to think his trucks get jigged more then your average ER ever would. So they'd be a good test of a truck being abused I'd think.