ok, so i see guys that have 91 or 91.5. i don' t know what the differences are. and when i went to the auto parts store today they had 2 diesels listed... a c code engine and an 8 code engine. since there is no c in my vin i would assume that it is an 8 code engine but i don't know what that means.... the vin is
1B7KM3680MS240980 if anyone can get more info out of that, can tell me where a site is that explains vin's, or has some sort of carfax report subscription or something like that... i am trying to learn as much about the truck and it's history as i can.

 

1991 are not intercooled 1991.5 have the intercooler

 

Here it goes at VIN decoding:
1=made in US
B=Dodge
7=Truck
K=8001-9000 GVW
M=Ram pickup/Chassis cab/Ramcharger (all 4X4)
3=350 Job Rated Truck
6=Conventional Cab
8=5.9L Turbo Diesel-non-intercooled
(C=5.9L w/intercooler)
0=Check Digit
M=1991
S=Dodge City assembly Plant
240980=sequential number

I hope this helps some

 

Dang, you beat me to it, Dave! You must be caught up on the steam engine work.

 

so, since it is non-intercooled does that mean it has a smaller radiator?

 

Naw, Just catchin' up on my reading and figured I could help
BTW your'e never caught up with a steamer.

 

Yup, the non i/c rad's are the lamer of the two designs. The newer units are also cross flow as opposed to top to bottom. This supposedly encourages better cooling. I've had my winter front on and fan OFF for weeks and my rad is truly a POS. I'd be surprised if more that 2/3 of the cores actually flow coolant at this point. Never seen more than 190. Granted I don't tow.

 

so the 89-91's have poor radiators? That gives me a good excuse to tell the wife it needs a new one. I was hopeing it would just freeze and crack so I could buy a new one. LOL Nothing like 20 degree temps and nothing but water in it. As long as the block has the heater keeping it toasty.

 

Hey there G1625S...I have to differ with you on the radiator. I purchased my 1991 W250 18 months ago with only 85,000 miles on her. The previous owner only pulled a "tootsie" 6'x8' landscape trailer. Never really worked the truck. I pull a 16' car trailer with my 1979 heavily off-road modified Jeep CJ-5 on it and I get good cooling performance from my radiator. I drive up and over alot of mountains, she get's hot struggling up some of them, but then cools very quickly hammering down the other side at 85mph. Just wish she had that overdrive gear, she's just a three speed but performs well for my needs.

 

Rick Bear: Welcome to DTR! You'll have to take my radiator comments with a grain of salt...though it is generally accepted that the newer style 'cross flow' rads cool better, the point I was trying to make was that, even WITH the 'inferior' radiator WITH a cold front and WITHOUT the cooling fan, I still run cool. Having said that, more cooling capacity is always better. I've only towed my 5er (10,000 pounds) a couple hundered miles, but they've been trouble free miles
Welcome again---get some pics of your truck up in your gallery! All first gen, all the time!
Greg

 

The 8th vin number or letter will always be the engine code.

 

I have the "lame" top flow and it works fine at this point...needle on the gage stays put even if I'm hammering it...heater blasts me out of the cab even on the really cold days. Wouldn't bother changing it as there are monuts, hoses, etc to mess with.