Approx. mpg on Chevy diesel??

[skobylenski]

So here's the deal, my parents are looking at (actually I'm looking at it for them, since its in New York) a 1994 Chevy 3500, 4x4, crew cab, long box, single rear wheel, 5 speed, 6. 5L diesel pickup. What sort of fuel mileage is typical of a truck like this? It has 130,000 miles on it (not that that really matters all that much). I'm not sure of the axle ratio, either.



Now I know, I've put in the good word for another Cummins, so I don't want to hear it about how much Chevy sucks and all that jazz and they've looked at one (a '90 4x2 with the 3 speed), which got about 17mpg, which they were obviously not impressed with since the Tahoe that will get replaced by the next truck gets 18mpg... . lol.



Anyway, I just want a ballpark figure that we could expect to see with this greyhound bus of a truck, since I know the axle ratio will make a difference to an extent.



Thanks, Scott

 

[ndurbin]

If it has a higher rear end it should do pretty good. One guy I know claims 25+ on a reg. basis, but I'm not sure about that.



I'm not going to bash Chevy's but I will pass on some information a reputable diesel mechanic gave me about 6. 5's. "If it runs good, get rid of it because something is about to go wrong. "



Nathan

 

[bmoeller]

The few I have driven ('92 anda '93), never got over 13. Although, that one you are looking at, should have an electronic fuel injection pump. So I can't say for sure on mileage, if they are comp. or not.



I don't recall the name of the box that controls the fuel inj. pump, but you'll want to move it away from the engine. There is kit that you can buy to move it. They don't like heat. '94 and '95 trucks had problems with that.



GMs aren't a favorite, but they are decent. I just don't like the IFS on the 4x4 trucks or the TLA that actuates the front axle. They are junk.



The 5spd, IIRC, is a NV4500. I like those. The one truck I drove had one. It had a granny low and O/D in it. Something like a 6. 03 low gear, or something close to that. They weren't used for more than that year, I think. Some had problems with 3rd gear. The one I drove had a slight problem with 3rd. A little hard to move into gear. The others went right in. The newer ones were in the neighborhood of 5. 42, or so. Don't recall for sure. Been a while.

 

[Rescue Ram]

I don't recall the name of the box that controls the fuel inj. pump, but you'll want to move it away from the engine. There is kit that you can buy to move it. They don't like heat. '94 and '95 trucks had problems with that.

It is called the Fuel Solenoid Device (FSD) or the Pump Mounted Driver (PMD). If you bite on this truck, you should take care of this right away, as the IP will croak in short order. If it has an intermittent no start after it is warmed up, or cuts out and dies while driving, the PMD and IP are most likely roasty toasty. Around $2100 or so if I remember right. This was a problem on everything from 94 up, though was a little better in 99-00 I understand.



Look to see if the IP has a green tag. GM extended the warranty to 120k miles or 6 or 7 years, can't remember for sure. It might make a difference for you, might not.



Our last 6. 5L was a K3500 4x4 auto with 4. 11's, I think. It would run 18 mpg or so on the open road.



Also, take a good look at the block. There were a bunch of blocks that were cast poorly, resulting in a crack in the water jacket around cylinder #8.



Keep a spare Oil Pressure Sensor (OPS) on hand. They gave me some trouble as well.



A compression test might be a good idea; make sure the head gasket is good. They can get some pretty good combustion temps due to the lack of an intercooler.



Hope this helps. Poke around the GM site and verify all the information I have given. I think it's mostly accurate, but like most of my brains, it has been rattling around unused in my head for some time. :-laf :-laf

 

[RGardner]

I had a buddy that owned on for a short while, it would overheat constantly! He did everything he could think of to fix it and finally traded it in on a Cummins!

 

[Cattletrkr]

I'd stay away from the 94-95's. Those two years weren't very good. Dad had a 95 that was a PITA. Wonderful driving truck, not much for towing. Dad's had an auto, maybe a stick would tow better. There's a lot of little things to check out, first would be the FSD or PMD. Ya definently want to be able to monitor FP somehow. I think dad's went thru 3-4 lift pump and a couple inj. pumps. All covered under GM's extended warranty, something dodge never did for lp's BTW. Dad's auto w/4. 10's almost never got over 16mpg. Usually 14. 5 seemed to be the norm. Got better mpg at 70 than it did at 60mph.

 

[PToombs]

Hey Scott,I drove a '95 C3500 service truck with an auto trans for 3 years. It got 10 to 12 MPG, but it weighed between 8 and 9k. When it ran, it ran great, when you had a problem, it was a big one. It stranded me up near Malone with the oil pressure switch problem, it hooks to the fuel pump somehow. Then the computer for the inj pump went, lucky to be close to the shop that time. They put the kit on and moved the unit up and fastened it to the top of the intake. they also said throw away that nice cover that says"TURBO", it holds the heat in. :{

 

[PKleine]

Keep a spare Oil Pressure Sensor (OPS) on hand. They gave me some trouble as well.

The reason for this is the oil pressure sensor controls the lift/transfer pump.



I have a 95 (P)Yukon with the 6. 5 td. In 111k miles it's been through 7 injection pumps. For some reason GMC doesn't want to do the right thing and provide the needed cooling for the PMD. So, as long as it's on them...



Good luck,



PK

 

[skobylenski]

Wow, thanks guys. Tons of great info. , this is why I love the TDR. I guess if the 'rents go for it, I'll be doing some work to make it run a little better. Definately something to think about when I go test drive it next week, lol. I'll be printing this thread out so I can remember all this info.



Thanks a million!