[A/S] GM 454

[Stan Nicholson <stan@xxxxxxxxxxx>]

Jonathan -

We've put about 6,000 miles on a '96 Suburban K2500 454 that we 
bought used a year ago.   Mileage agrees exactly with Dick Martin's - 
11 mpg solo and 8 towing.  Our Airstream is also 7200 lbs, and the 
Sub has the 3.73 differentials.  The engine has shown absolutely no 
signs of overheating, even on long 6% grades, and speed & muscle are 
more than acceptable. I did install an aluminum high capacity trans 
pan with temp gauge, and found the trans temp still got up in the 
230-240 range on a 6% grade.  The easiest way to get additional trans 
cooling, I found, is to replace the factory cooler, rather than 
daisy-chaining them - there's just enough room for a stacked-plate 
design that's twice as large as the OEM cooler.  I'll check its 
performance next week when we tow to the Hobo Rally.

As a mechanic you know that '96 was the first year of the Vortec 
engines with port fuel injection - to my mind that makes '96 the 
oldest 454 worth considering.

Another thought - the tow rating on the '96 (and probably thru '99) 
K2500 454s is 8000 pounds.  It does bother me a bit that pulling a 
trailer which scales at 7200, plus carrying a lot of stuff and 
options in the (loaded) Suburban, leaves about zero extra capability 
(although the Suburban is quite a ways away from its GVW maximum). 
So my fantasy tow vehicle would be a crew cab short bed with 
Duramax/Allison, both because of the tow rating margin, the muscle, 
the improved brakes, and general "cool" factor.

But compared to a 350 Suburban as an alternative, there's absolutely 
no question that a 454's a better bet.  Just check the tow rating  on 
a 2500 Suburban with the 350.

Stan