Hello all. I've hung around a few times here asking advice on what to buy (or not) and trying to learn what I could searching through all the topics. Thanks to all who replied.

Well I picked up my um... "new" truck yesterday. An '89 Grumman P-30 with a 6.2 and drove it 160 highway miles home. Yup, it made it.

A few questions if I may; No idea how many miles are on this thing or how long it may have been sitting. (Odo says 35,000. Yeah right.) It started (though sounded like hell and stumbled for a few minutes) but then smoothed out. By the end of the journey it seemed to run MUCH better than the beginning. Now it idles smooth and quiet and pulls off of stop lights quite nicely although it's certainly not a 350 gas.

Highway power was horrible. Probably has gearing in the 4.xx range (as it was built for city postal delivery) and there was a "spot" at about 55mph where it seemed to run happy. Just before this speed the go pedal seemed to add power fairly linear, but above it the return appeared to diminish. I was afraid to push it for because of it's unknown history and a broken temp gauge so I have no idea as to top speed or what RPM it was running at (need a tach too)

So... The identical truck with the 292 is 5400Lb dry. Guessing this would be 6000? So enough of the long winded background and to the questions.

What is a "nice" sustained RPM this engine should/could be run at on the highway?
What is the redline?
Where does it make the bulk of it's power?
What is a safe "passing" red line?
What is the operating coolant temperature? Same as gas at 195?
Is this engine governed?
What is the proper oil pressure at various engine speeds?

At the beginning of the run the truck felt like it was going to self destruct with road noise, vibration, and I think a bad driveshaft sling bearing. It also felt like it might have been missing a cylinder - but at the end it sounded really good at 55. Any comments? Internal combustion engines generally dont heal themselves. (Man I wish!)

Any suggestions on a GOOD 6.2 manual? I'm not afraid to tear into anything - but don't want to do it with one of those crappy Haines manuals. Friend following me said he could smell "rich" diesel from exhaust. Any clues here or is this normal?

I guess all I really want is many happy miles at 70MPH. (120Km/h) Am I looking at a rear end swap for this or will this engine do that?

I estimate my milage wasn't too shabby at about 18MPG - but again it seemed to be worse at the start and increased.

Guess I'm just looking for any comments that you may have. Overall I'd say this truck was well cared for - I know Grummans quite well - and their signs of general beatings and neglect.

Oh... One more stupid question! Let's say for the heck of it that it really did only pile up 35000 in 15 years (as a yard truck?) then that would mean huge hours of idling. In a perfect world would an engine like this rather see it's life at idle or at 3/4 top speed? how do diesels wear at idle and how many gallons per hour would I expect it to consume at idle?

Thanks for your time.
Jim.

Welcome,

Start with the basics, check the air filter, replace the fuel filter, change the oil, figure out what gear ratio you actually have. 6.2's like to run at a certain speed and overcoming that speed won't happen if you are overcome by outside factors such as wind resistance. A few power enhancers could help, open up the exhaust, larger pipe and free flowing muffler, turn up the fuel, open up the intake air path. These engines are governed, they make their best HP at about 2800 to 3000 rpms and best torque at about 1800 to 2000 rpm's. What size tires are you running? These engines can do a respectable job, but everything in the drivetrain needs to be matched. A turbo makes all the difference in the world. My 6.2's would always out perform a 350 gasser any day of the week when driven at the same rpm's.:eek:

Jim, bring that hot rod over and I'll look it over for ya.
So many things to discuss with a new diesel owner and new truck.
Even old neglected 6.2s can be quite good work horses, but don't expect not to have to nurse her back to good health.
Do as D Cam suggested, start with the basics, fresh fluids/filters, and fix your instruments so you don't damage anything. Then we can more easily guide you on how to make it run right.

TDG, where are you in Ontario?

Oakville/Burlington, west of Toronto

how far do you figure from Niagara falls? (I can get there in a little less than 2 hours)

I can get to the border in ~45min, depending on traffic.

Jim, bring that hot rod over and I'll look it over for ya.

I'll certainly take you up on the offer but it won't be on the road again until the end of summer. I'm going to focus on the body first and a few um... Mods that I have planned (I actually bought it as a project vehicle) first. So I'm not bothering with plates/insurance yet. My neighbor sure does think it's purdy though sitting in the back yard!

Overall I was pretty happy with fuel consumption bringing it home. My original plan when I bought it was a 305TBI swap (as a complete running but rotted doner van/pickup here as you know can be found for a song) but I kinda like the way it drove and the milage was nice so the 6.2 is going to stay for sure. Although I'm kind of looking out of the corner of my eye at perhaps a 4L80E instead of the 400 behind it (for the OD). Just have to look at production figures and see how available and reasonable they are.

D. Cam: The eventual tire size will come in at just under 31" I think. (LT265-75-16 IIRC coming off my other truck - about a half inch taller than what's there now. I wouldn't attempt a turbo upgrade without a complete doner engine (I'm finally old enough to have learned a thing or two - Heh-heh.) so that's unlikely to happen.