One of my bucket trucks is a 2007 F550 4x4 with Altec lift and the cab is torched from an electrical fire. Motor is good and uncertain about trans at this point. Good thing is I had an entire 2004 basket case F550 2wd cab chassis sitting around collecting dust for this very reason. The fire burned pretty good and am considering placing the '04 cab on the 07 chassis (both 6.0). Aside from the 2wd and 4x4 dynamics, i wonder if the heat exposure from this blaze is the structural integrity questionable?. These frames are pretty thick and yes the cab was torched to bare metal inside. Might just remove the boom onto the 04 chassis if necessarry. thanks everyone, Ron

 

Did the fire actually "touch" the frame anywhere?

I'm certainly no expert, but if it's just the cab floor that got scorched, there is a pretty good amount of "air space" between the cab floor and the frame. I would think it would take quite a bit more heat at the frame than what you are describing unless the frame is scorched or discolored by heat somewhere.

 

Modern frames are heat treated at the factory. I'm no metallurgist, so I don't know the effects of buggering up the heat treating would be. No it's not going to bend or collapse as you drive down the road, but I'm guessing it may perform differently in a wreck. It also might have vibration issues as the resonance frequency of the frame may have been changed.

I'd triple check everything to make sure none of the brake or electrical lines were damaged on the donor frame and go for it. But it's possible it won't drive or ride the same if the frame got hot.

 

I'd do it as long as all the lines were not melted and you don't notice any significant discoloration.

 

Thanks for all the replies and concern on this thread. To provide a little more clarity this is a 4x4 and where the linkage for transfer case comes up through the floor was burned and am replacing the trans harness, as well as brake lines just to be safe. As well the a/c system and heater core were melted extensively with minor intrusion into engine compartment.The truck itself is used in a local setting with minimal driving and at speeds less than 45 mph. After some study on the effects of fire I learned that the heat temp is in the 1300 degree range. Perhaps the effects of the heat might have helped in the hardening the frame although it would seem with such an abrupt cool down from the water sprayed to put out fire perhaps the metal might become brittle? Anyway the cab is coming off so eevry part on the cab is a non concern.

 

1300° would certainly have affected the heat treating of the frame if it got that hot, but it's not likely if the fire was contained in the cab above it. I think the only chance someone will be able to tell the difference would be if it were wrecked or maybe some vibration on the highway.

I think you'll be fine.

 

thans for the vote of confidence Tom, it also will be interesting to find if the transmission fluid boiled of affected the seals as well the torque converter. Ill devote some more time to study of how metal is heat treated

 

The best thing to do is take it to a body shop and have them put it on a frame machine.most shop have laser style measuring system. They will be able to tell you if the frame got hot enough to sag.I seriously doubt it did those frames are heavy duty and would have to be exposed to some high heat for a good while to do any damage to the metal integrity. Body shop is only for your peace of mind.

 

My uncle rebuilt an 84 f350 back in the 80's that had a completely gutted cab and front end from a fire. the origional engine, trans, and frame were reused without any problems. Though it was never involved in a wreck.

 

what kind of transmission was in the f350? auto or 5 speed?

 

84 would have been either a 4 speed or C-6.

my 04 was in a fire when it had 12,000 miles on it. complete cab gut just like yours.
i dropped a new cab/nose on the frame, purged the old stale gas out of the fuel rails, and have put close to 3,000 miles on it so far this summer. the fire did not even melt the grease off the frame where the mechanic cleaned his grease gun tip.

 

wow interesting to learn all this stuff, thought for sure there was a slight possibility that this will be successfull. The more that I'm finding is that it should be fairly easy. Did your cab fire get into the heater core area and into en gine at all?

 

it actually started outside the passenger side tire in a crown vic police car that was set on fire by a person mad at the town cops.
burned the passenger side tire, passenger fender, grill radiator, passenger side wiring, heat/ac box, broke the passenger side window and set the headliner on fire, which dripped down and set the rest of the interior on fire.
and i know it went down this way because the original arson of the crown vic was caught on video, and they watched it telegraph into the truck before the fire dept got there.
when i got it the person that bought it at auction did a halfassed repair. i saw all the cut wires and rigging that was done and just put the new cab on it to solve all the problems.

 

Tom is your 04 and automatic trans?

 

Does the frame still have any paint on it? I ask because the paint is going to fail with high heat long before the frame is affected, so if you still have paint on the top of the frame, I'd say you're good to go. Same with melted plastic dripping on the frame- that plastic will burn up rather than drip if the heat is anywhere close to affecting the frame.