Engine/Transmission (1998.5 - 2002) Need a refresh

[Matt Hannink]

Hey all. It's been 13ish years since I had a cummins powered truck and i need some refreshment/update on some things. I don't own a cummins again just yet, but I have my eye on one. Even if this one I'm looking at doesn't come through I'll be looking for one like it.

The truck I'm looking at is an 02 quad cab short bed 6 speed 4x4. 24v cummins, obviously. My goal is to make the truck absolutely solid and dependable. I know they are pretty damn good, but can be made better.

Usage will be daily driving and occasional towing. Rotating the truck out with my other diesel so neither sits too much.

So what's changed and/or improved in the last decade? I seem to remember the late 2nd gens had in tank pumps. When did that start? Are they reliable, how does the vp44 hold up with them. I know the nv5600 had teething issues. What are the fixes? Is it like the getrag and put an extra quart or 2 of oil in through the shift tower? What year did the do away with the CAD on the front axle?

How about performance? Planning on modding this thing eventually. Is smarty the best tuner still? Is mach still the best injector? This vco vs sac is new to me. What is out there for turbos now?

 

[petersonj]

So what's changed and/or improved in the last decade? I seem to remember the late 2nd gens had in tank pumps. When did that start? Are they reliable, how does the vp44 hold up with them.

The VP44 trucks never came with in-tank lift pumps. Many were installed by the dealer under warranty when a VP44 was replaced under warranty. There are no real issues with the in-tank lift pump. Don't get caught up in the lift pump / VP44 myths - all that is needed for the VP44 to be happy is a positive fuel supply pressure measured at the inlet of the VP44 when the engine is under full power.

I will use my truck as an example. The VP44 was replaced and in-tank lift pump was installed by a dealer under warranty at 87,000 miles. The new in-tank lift pump pressure was 6 psi at idle and 3 psi under full power. Well over 150,000 miles later, I removed the in-tank lift pump and installed a used frame mounted lift pump. The in-tank lift pump was still operating fine - I just wanted an easy repair in case of a lift pump failure on the road. The replacement VP44 has now logged over 300,000 miles and is still operating fine.

I know the nv5600 had teething issues. What are the fixes? Is it like the getrag and put an extra quart or 2 of oil in through the shift tower?

The NV5600 has a good reputation. Some people add an extra quart to the transmission ensure a particular bearing in the rear part of the transmission gets better lubrication. I have done that once or twice, but I personally don't think it is necessary. It is important to periodically check the fluid level to make sure that it is full, though. I occasionally tow heavy for periods of time. My NV5600 has logged 394,000 miles with no issues, other than a leaking rear seal. I replaced the seal when doing a clutch job.

What year did the do away with the CAD on the front axle?

I don't think it is associated with a particular year. My truck is a 2002 (build date Oct. 2001) with a CAD unit. My brother-in-law's 2002 (build date May, 2002) with an automatic transmission does not have a CAD unit. Another fellow has a 2001 with an automatic and it also does not have a CAD unit. You will need to look under the truck and see for yourself.

As far as the Smarty S06 tuner, I think it is a very effective tuner for the VP44 trucks. Just remember that is designed for stock injectors and has a maximum of 60 horsepower gain. I am fine with this because it is a very strong performer in the low to mid rpm range, which is where most of us operate our engines. The tuner is an excellent performer when used with a manual transmission. The tuner is easy to use and does not need to be plugged in after a tune is set. Also, engine codes can be checked and cleared, and the speedometer can be re-calibrated to match tire size.

- John

 

[Matt Hannink]

The VP44 trucks never came with in-tank lift pumps. Many were installed by the dealer under warranty when a VP44 was replaced under warranty. There are no real issues with the in-tank lift pump. Don't get caught up in the lift pump / VP44 myths - all that is needed for the VP44 to be happy is a positive fuel supply pressure measured at the inlet of the VP44 when the engine is under full power.

I will use my truck as an example. The VP44 was replaced and in-tank lift pump was installed by a dealer under warranty at 87,000 miles. The new in-tank lift pump pressure was 6 psi at idle and 3 psi under full power. Well over 150,000 miles later, I removed the in-tank lift pump and installed a used frame mounted lift pump. The in-tank lift pump was still operating fine - I just wanted an easy repair in case of a lift pump failure on the road. The replacement VP44 has now logged over 300,000 miles and is still operating fine.


The NV5600 has a good reputation. Some people add an extra quart to the transmission ensure a particular bearing in the rear part of the transmission gets better lubrication. I have done that once or twice, but I personally don't think it is necessary. It is important to periodically check the fluid level to make sure that it is full, though. I occasionally tow heavy for periods of time. My NV5600 has logged 394,000 miles with no issues, other than a leaking rear seal. I replaced the seal when doing a clutch job.


I don't think it is associated with a particular year. My truck is a 2002 (build date Oct. 2001) with a CAD unit. My brother-in-law's 2002 (build date May, 2002) with an automatic transmission does not have a CAD unit. Another fellow has a 2001 with an automatic and it also does not have a CAD unit. You will need to look under the truck and see for yourself.


As far as the Smarty S06 tuner, I think it is a very effective tuner for the VP44 trucks. Just remember that is designed for stock injectors and has a maximum of 60 horsepower gain. I am fine with this because it is a very strong performer in the low to mid rpm range, which is where most of us operate our engines. The tuner is an excellent performer when used with a manual transmission. The tuner is easy to use and does not need to be plugged in after a tune is set. Also, engine codes can be checked and cleared, and the speedometer can be re-calibrated to match tire size.

- John

Ok, that's good to know. I'm leaning towards doing a fass right off for peace of mind and easier filter changes. Always hated doing fuel filters in these trucks.

I know they are pretty good. I just vaguely recall some issues with the sychros or something. Seemed that a little extra high quality oil seemed to do the trick.

I was just curious. No cad would be nice.

I remember it was the cats meow at one time. How's the touch version? I was looking them up and it's kind of neat.

 

[petersonj]

There is not much in the way of benefits using Smarty Touch on the 98.5 - 02 VP44 trucks. You cannot change power on the fly. You won't have many gauge choices as the VP44 trucks have a limited communications system - example: no lift pump pressure gauge, no VP44 injection pressure gauge, no AC pressure gauge, boost gauge will not be accurate, etc. You can have an EGT gauge, but you must purchase the sensor separately.

The Smarty S06 is less expensive and has the same adjustable parameters for fueling, torque management, and timing as the Smarty Touch.

No cad would be nice.

CAD or no CAD is personal preference. I am very happy to have one. Modifying the system with a vacuum control valve to have the ability to select low range, two wheel drive is a great feature for backing trailers on dry surfaces or paved surfaces in tight areas. No wheel hop or stress on the drive train, and backing with the engine idling gives lots of time for steering corrections.

- John

 

[Matt Hannink]

There is not much in the way of benefits using Smarty Touch on the 98.5 - 02 VP44 trucks. You cannot change power on the fly. You won't have many gauge choices as the VP44 trucks have a limited communications system - example: no lift pump pressure gauge, no VP44 injection pressure gauge, no AC pressure gauge, boost gauge will not be accurate, etc. You can have an EGT gauge, but you must purchase the sensor separately.

The Smarty S06 is less expensive and has the same adjustable parameters for fueling, torque management, and timing as the Smarty Touch.



CAD or no CAD is personal preference. I am very happy to have one. Modifying the system with a vacuum control valve to have the ability to select low range, two wheel drive is a great feature for backing trailers on dry surfaces or paved surfaces in tight areas. No wheel hop or stress on the drive train, and backing with the engine idling gives lots of time for steering corrections.

- John

- John

Good point on the smarty.

You're right about the CAD. Most of the dodges i had, had one. Got rid of the vacuum controls and installed the cable. Was great after that. I was mostly just curious when it ended.

 

[Matt Hannink]

So it looks like the deal is going to go through. Next week I should be picking up the cleanest 2nd gen I've seen in a long time. It's a 2002 quad cab short bed 4x4 with all the options. What I'm trying to figure out is the engine. Is it a so or ho? The vin is a 6 but it has the 6 spd. I keep reading that all ho engines have the 6 spd. My question is, do all 6 spd have the ho? Or could you get the so and a 6 spd in 2002?

 

[petersonj]

To my knowledge, if the truck came from the factory in 2002 with a NV5600 six speed, it is an HO engine. In 2002, SO engines were paired with the 47RE 4sp auto or the NV4500 5 spd manual transmission.

Engine Output SO - 235 hp, 460 lb/ft torque - 47RE 4sp auto, NV4500 5 spd manual
Engine Output HO - 245 HP, 505 lb/ft torque - NV5600 6 spd manual

There are different ways to verify. The serial number on the VP44 pump can be checked on line, or the Cummins data plate on the engine will verify horsepower, or you can go on line and use the truck VIN to identify the engine output.

Example for my truck: 5.9L TD HO ENG(ETH)/6SPD M/T NV5600

Enjoy your new to you truck!


- John

 

[Matt Hannink]

To my knowledge, if the truck came from the factory in 2002 with a NV5600 six speed, it is an HO engine. In 2002, SO engines were paired with the 47RE 4sp auto or the NV4500 5 spd manual transmission.

Engine Output SO - 235 hp, 460 lb/ft torque - 47RE 4sp auto, NV4500 5 spd manual
Engine Output HO - 245 HP, 505 lb/ft torque - NV5600 6 spd manual

There are different ways to verify. The serial number on the VP44 pump can be checked on line, or the Cummins data plate on the engine will verify horsepower, or you can go on line and use the truck VIN to identify the engine output.

Example for my truck: 5.9L TD HO ENG(ETH)/6SPD M/T NV5600

Enjoy your new to you truck!


- John

What is the ETH part? I've been seeing that reference. There's another one for the SO engine but I can't recall it right now.

 

[Chief USA]

If memory serves me (and it rarely does) I believe:

ETH = The order code for High Output (HO) diesel.
DEE = The order code for 6 speed manual transmission.
ETC = The order code for Standard Output diesel.

 

[Matt Hannink]

Are those on the truck somewhere?

 

[petersonj]

Are those on the truck somewhere?

I will look mine over tomorrow. My truck is a 2002 HO with an NV5600.

- John

 

[Signal73]

Under the hood had one by the latch, was there one in the glove box too? I forgot.

 

[petersonj]

Well, I tried to photograph the engine information on the driver side of the gear case cover, but it's just not accessible, so no help from me.

- John

 

[Matt Hannink]

Thanks for the help. I'll get into this much more when I get the truck home. The plan right now is to go get it on Wednesday.

 

[Shelby Griggs]

If memory serves me (and it rarely does) I believe:

ETH = The order code for High Output (HO) diesel.
DEE = The order code for 6 speed manual transmission.
ETC = The order code for Standard Output diesel.

Those are correct to best of my memory too!