Do it yourself.

It's not bad at all. Just make sure you keep it clean and follow the directions. Everything torques at low inch lb. specifications.

Here's what mine looked like this winter when I did it. Towed awesome all summer with no pinging.

CHECK YOUR OIL!!!

Ok, so if he has a intake leak (and it sounds like a bad one to boot) what are the chances that he'll lean the motor and burn a valve? The injector is right at the valve so he'll be ok, right?

2001 360 40K and I use 89 to tow..Guess I
used 93 last week on 500 mile tow after pinging
on 89..I have 5 yr 75K service contract..

The injection system can compensate for the extra air to a point. I have not seen one damaged due to lean run. From what I have seen I would guess that 50-60% of these engines are leaking-the rest have already been fixed.:(

Pinging=detonation

Detonation=#1 killer to motors

Fix the problem before you have to worry about blowing the motor. Why keep abusing the pistons when you can fix the problem? He won't be OK after a while, and who knows how long that may be.

Waterfoul

I have a 1999 Durango with the 360, and if I run anything other than 92 octane it spark knocks bad!! It has basically done this since new, have 41,000 on it now. Always seemed funny to me, I thought the manual says it is ok to run 87 octane. Even on 89 octane it rattles like crazy, towing or not. Getting ready to replace it with a Powerstroke Diesel, then I will not pay attention to the noise.:D :D

Deffinatelly plenum intake gasket

Before you get to far with repairs here let me ask one stupid question.... Did you or anyone else ever change the stock computer "chip" to an aftermarket HP "Chip"?... if so.... thats a real problem under tow.....

GRH
 

Never changed the chip.
Thought about it, but never did.
The stuff I tow isn't all that heavy, under 5500 lbs, so I never really had any issues on power.
The pinging issue is caused by the plenum leak, he can try everything from av gas to chips to a cooler thermostat, they'll all help, but they are just band aids to the inevitible.

Waterfoul,
Bigwavz might be right. My 2000 Ram with the 360 had a ping about a year ago that was really pissing me off. It ended up being a timing ping. Go have your timing checked.

Good Luck ,
Bunt:)