Test drove a 1990 F250, cracked firewall? On an automatic?

[RustyBuns]

So I test drove a F250 4x4 today and I noticed it was a crack (or 2, don't remember) on the firewall a few inches away from the brake booster. I know there is an issue with the manual transmission trucks with cracking, but anybody heard about it on a automatic? I also noticed that there was a good vibration in the dash area that went away as soon as you gave it the slightest bit of throttle. I'm just wondering if these issues are related. I'd hate to buy a truck then have the brake pedal shoot through the firewall in a panic stop. Plus, that vibration is pretty loud.

IIRC the crack was about halfway from where the drivers side valve cover is and the break booster.

Thanks in advance guys!

 

[Optikalillushun]

they firewall TSB doesnt actually deal with a crack...its the two plates seperating...which can lead to a crack but the TSB is for firewall seperation.

 

[LCAM-01XA]

These engines vibrate pretty strong at idle, but the moment you give it a bit throttle they smoothen out - I have a filter hanging off to the side of mine and I can see it shake at idle, once I'm past 750 rpms tho the thing gets absolutely still, hardly any vibrations at all, and definitely nothing I can visibly notice. So I probably wouldn't worry much about the idle vibrations of that truck, but that firewall crack sounds weird, as that's supposed to be a bolt-action thing cause of the clutch pedal.

 

[RustyBuns]

Thanks for the replies, guys. He decided not to sell after all, so back to square one. Least I got my 6.2 to drive in the meantime.

 

[icanfixall]

Vibration comes from 2 real places on these motors. First the Mahle pistons can be as much as 14 grams differance from piston and still run fine as per the Mahle engineers I spoke with last year. I don't feel 14 grams is something I would run with. My pistons are 1/4 to 1/3 gram differance in weight. The other vibration area is the cam gear. The early gears created a vibration so the newer gears all have a balance lug cast into them and they don't have the 2 threaded holes for attaching the removal tool.

 

[1Turbo10]

Anyone have a part number for that fire wall kit? Just noticed mine is broken at the cluch. Thanks