04 Isuzu NPR gasser, what do I need to know?

[01rangerxl]

We had a box truck crisis at work and needed one with a liftgate ASAP, and after a week of looking all I really found that was "cheap" was an 04 Isuzu NPR with a GM 6.0 and I assume 4L80E (it looks like one). My boss went ahead and bought it yesterday, and it was put to work all day today. It has 245k, but was clearly well maintained, drives great, and everything works.

The previous owner mentioned that AC is problematic in these and he's had to get it repaired a couple times over the past 10 years. It worked great when I test drove it. He also mentioned that it had an aftermarket radio because the original had a weird short that somehow made the engine stall, but since replacement it has been fine.

Anything I need to be aware of as far as maintenance or common problems? Not worried about the 6.0/4L80E, that's why we got it, but I have no experience with NPRs before this. Our "free" Mitsubishi Fuso diesel has been unproductive and expensive, so I hope the NPR won't be. We usually use Express/Savana 3500s, but there were no cheap ones with liftgates that were any good.

 

[nthach]

If you're using GM vans at work, the NPR will be more or less the same with the drivetrain. It seems like these are really popular for bigger box vans and they can take some abuse.


Any idea why the AC or radio went out? The AC system on those is a weird mix of Delphi on the compressor side and probably Denso or Calsonic on the cab side. It's weird to hear about a radio causing engine issues on Japanese trucks, unless it was introducing noise into the engine/trans harness.

 

[01rangerxl]

The PO said the compressor had been replaced for at least one of the AC repairs. As far as the radio issue, he said they had a problem with it stalling, sent it to a shop, the shop figured out it was this weird short, replaced the radio, and it has never been an issue again. Go figure. The PO didn't do any work on it himself, he sent it to the shop. By the looks of his company, he doesn't skimp on that kind of stuff either. He had the truck from 2009/38k until now/245k.

 

[Chris142]

If it has the condenser under the passenger side ahead of the front wheel the fan motors fail and burn the compressor up.

 

[01rangerxl]

It does, good to know.

 

[Jarlaxle]

It will give a miserable, kidney-hammering ride vaguely reminiscent of an old cement truck...the huge windshield and engine heat pouring through the floor means the driver will BAKE, evcen with the (inadequate) A/C working. Electrical system is a weird GM/Isuzu hybrid.

Might be a good idea to change the trans fluid and filter, and possibly power-wash the glop out of the cooler.

Check the battery and connections. These trucks have the box on the frame, and it is frequently absolutely LOADED with glop from the front tire. The plastic housing gets brittle and comes apart after a while, especially with lots of sun. Since it has a power tailgate, get the biggest battery that will fit the box!

If it has 16" wheels with 215/85R16 tires (an NPR probably does), run them at max pressure (should be 80psi) in back.

It's a 50/50 chance whether the parking brake actually works...the previous drivers may not have used it! (Unless the gate only works with the brake on.) Also note: with a power gate, it probably spent LOTS of time idling to run it.

 

[nascarnation]

You're actually cutting edge.
My daily UPS truck is now with a GM 6.0 gasser where for years they were Cummins B diesels.
I think the latest generation diesels are just too expensive to keep running and don't pay back with fuel savings.

 

[SatinSilver]

How do these compare to a Hino truck? They look and seem about the same but just curious.

 

[JTK]

Originally Posted by nascarnation
You're actually cutting edge.
My daily UPS truck is now with a GM 6.0 gasser where for years they were Cummins B diesels.
I think the latest generation diesels are just too expensive to keep running and don't pay back with fuel savings.


I bet you're right on. It's not cost effective for them to run diesels in this application anymore. I was curious to what the gas engine was in these now, but now that you mention it, they do sound like a GM 6.0.

In regards to the Isuzu box trucks, the last gasser I drove was a small block chevy many years ago. Prior to that, around 1990, I worked for a large rental car company that also rented Isuzu box trucks. The smaller one was a 4cyl turbo diesel, the larger (30 footer?) was an inline 6 turbo diesel. It was pretty funny jamming around in those when I was 19-20yrs old and had zero experience driving anything that size.

 

[ls1mike]

Originally Posted by JTK
Originally Posted by nascarnation
You're actually cutting edge.
My daily UPS truck is now with a GM 6.0 gasser where for years they were Cummins B diesels.
I think the latest generation diesels are just too expensive to keep running and don't pay back with fuel savings.


I bet you're right on. It's not cost effective for them to run diesels in this application anymore. I was curious to what the gas engine was in these now, but now that you mention it, they do sound like a GM 6.0.

.


I heard one coming down my street to deliver some part to me. Sure was a GM 6.0. They have a pretty throaty exhaust on them.
I know the sound as I few LS based cars.

The 6.0 does really well for longevity.

 

[01rangerxl]

Originally Posted by Jarlaxle
It will give a miserable, kidney-hammering ride vaguely reminiscent of an old cement truck...the huge windshield and engine heat pouring through the floor means the driver will BAKE, evcen with the (inadequate) A/C working. Electrical system is a weird GM/Isuzu hybrid.

Might be a good idea to change the trans fluid and filter, and possibly power-wash the glop out of the cooler.

Check the battery and connections. These trucks have the box on the frame, and it is frequently absolutely LOADED with glop from the front tire. The plastic housing gets brittle and comes apart after a while, especially with lots of sun. Since it has a power tailgate, get the biggest battery that will fit the box!

If it has 16" wheels with 215/85R16 tires (an NPR probably does), run them at max pressure (should be 80psi) in back.

It's a 50/50 chance whether the parking brake actually works...the previous drivers may not have used it! (Unless the gate only works with the brake on.) Also note: with a power gate, it probably spent LOTS of time idling to run it.


Luckily for our drivers they won't usually be making long trips in it and different people will be driving it throughout the day, so no one person is going to be stuck in it for hours (usually).

I did notice that a lot of things seem like they could get splashed by the front wheels. The underside of this one looks like it was kept pretty clean. This one has 19.5" wheels.

The parking brake seems to be working, though I haven't tried it on a steep hill.

Originally Posted by SatinSilver
How do these compare to a Hino truck? They look and seem about the same but just curious.


Never driven a Hino, but that's what the previous owner replaced the Isuzu with.

 

[clinebarger]

The NPR-HD has 19.5" tires.

They are good commercial trucks, The Isuzu specific parts are quite expensive.

 

[nthach]

Originally Posted by SatinSilver
How do these compare to a Hino truck? They look and seem about the same but just curious.

Hinos are different - all diesel with a hybrid option and it seems to have somewhat better fit and finish.The cabovers are made in Japan, but their conventional trucks are built in W. Virginia.

Hino is a part of the Toyota Group, and coincidentally they do build major parts for the Tacoma and Tundra.