Just received all of the technical data and parts information from Joe
Mondello. If some of you remember I had several conversations with him via
telephone recently about the 455 engine and other parts of the GMC
motorhome. I have known about him for years, from the hotrod days, but
honestly did not know of his involvement in the GMC motorhome part. Wow!
Was I surprised at the wealth of ideas and parts available to us through
him. He not only gives specific recommendations but backs it up with facts
to support it.
Once example. I use Castrol 10W-30 motor oil in the 455. I have noticed
that when it idles the oil pressure drops almost to 0!. Never concerned me
yet since the engine is so smooth and idles so nice, with no noise in the
rockers etc.
Guess what his tech data says? DON'T USE 10W-30 MOTOROIL in the 455! Why?
large diameter rod and main bearing surfaces, with oil at 195-210 degrees it
is very difficult to fill the area between the mating parts. The oil
becomes so thin that the oil pump cannot supply oil fast enough to keep the
oil pressure up. He recommends 20W-50 motoroil, unless you drive in the
winter.He says that we should have 35-45 # of oil pressure at idle and 55-65
at full throttle. And guess what? He recommends mobil 1!!! No engine
failures for him while using it.
remember the discussion we had on thermostats? He recommends 180 degrees
for non smog engines and 195 degrees for smoggers.
And finally he has a cast iron water pump that delivers 30% more flow at
idle and 20% more flow at 3500 RPM than any other pumpo on the market
(Mondello part # WP-455)
Have to go back to reading now. to interesting.
Tom & Marg Warner
Vernon Center NY
1976 palmbeach
Mondello. If some of you remember I had several conversations with him via
telephone recently about the 455 engine and other parts of the GMC
motorhome. I have known about him for years, from the hotrod days, but
honestly did not know of his involvement in the GMC motorhome part. Wow!
Was I surprised at the wealth of ideas and parts available to us through
him. He not only gives specific recommendations but backs it up with facts
to support it.
Once example. I use Castrol 10W-30 motor oil in the 455. I have noticed
that when it idles the oil pressure drops almost to 0!. Never concerned me
yet since the engine is so smooth and idles so nice, with no noise in the
rockers etc.
Guess what his tech data says? DON'T USE 10W-30 MOTOROIL in the 455! Why?
large diameter rod and main bearing surfaces, with oil at 195-210 degrees it
is very difficult to fill the area between the mating parts. The oil
becomes so thin that the oil pump cannot supply oil fast enough to keep the
oil pressure up. He recommends 20W-50 motoroil, unless you drive in the
winter.He says that we should have 35-45 # of oil pressure at idle and 55-65
at full throttle. And guess what? He recommends mobil 1!!! No engine
failures for him while using it.
remember the discussion we had on thermostats? He recommends 180 degrees
for non smog engines and 195 degrees for smoggers.
And finally he has a cast iron water pump that delivers 30% more flow at
idle and 20% more flow at 3500 RPM than any other pumpo on the market
(Mondello part # WP-455)
Have to go back to reading now. to interesting.
Tom & Marg Warner
Vernon Center NY
1976 palmbeach