2009 Supernova 6400 Engine/System upgrades?

[CBerg3]

Hey all!! I’ll try not to make this too long-

We recently got a new to us 2009 supernova 6400. These forums have been so helpful!
We drove it from Texas to Maryland the last 2 months, and unfortunately had to use 2 tow trucks along the way- but found out it was the wiring plug to the ECM, (after we had a new ECM and FICM put In, and then it happened again)

We REALLY love this model for our family- we have searched for a year for this sleeping/bathroom configuration, in a diesel, and we want it to work, but my husband is uneasy after the breakdowns and it took us being stuck with no real answers.

We would love to do upgrades on the engine/ system to make it more reliable as we want to take it out for 6 plus months. We were hoping for any advice from the owners on here that have had it for a while, and that have learned from experience- are there basic things that we can do to upgrade it that may have had problems in the past or certain things that we need to be checking regularly that are unique to this rig?

I know that’s a very big question so we’re just looking for tips after reading so much online about these engines and systems. It sounds like that they can have some problems if you don’t get a few things upgraded, but we wanted to ask our friends here with the same rig as us before we move forward!!

 

[clarkeishere]

hello and welcome to the supernova club. Long list of engine upgrades I've been towed a few times myself. I take it you have the vt365. Have ARP head studs installed. in the battery box there is a 40 amp fuse the fuse holder is junk. buy a maxi fuse holder and fuse for that spot. Ground wire connector in the same spot is junk do away with it and wire straight. Under the engine, close to the crossmember is a wire connector that goes to the ECM, cut the connector out and use butt splice connectors in its place. close to the fuse panel tight against the firewall is a four-prong connector that I had fell. Young man at the international dealership use butterfly connectors and fix that problem. The fuel pump and the power steering pump or one unit. this unit is driven by gear in the in the oil sump area of the engine. I had the fuel pump diaphragm leaking fuel into my oil. To fix this I did away with that particular lift pump and installed an electric pump with extra filters I think it was made by fast.

At one point I was so upset that I wanted to do a swap to something different motor wise. like you I love my supernova.

I believe and hope that I have all of my bugs worked out. Also added air suspension so it rides a lot better.

if you need help questions please feel free to reach out to me via email at [email protected]

 

[Madkel]

Greetings,
Please share more details about what issues exactly you are experiencing. That would help.

In the meantime, let me share our experiences...
My Wife and I purchased a 2008 SuperNova 6400 in February of 2024. We too love the layout and the strength of the International Chassis. It has about 46,000 miles on it and it has never left us stranded.
It is not a powerhouse, hills are slow (About 35 to 45 MPH) but on the flats it will do 65 MPH which i find to be a comfortable pace.

We purchased it in Salt Lake City and drove it home in 2 days to the San Diego California area where we live.

However, after a trip to Arizona and Carson City Nevada towing about 3500 lbs, i noticed that at elevation (Above 4,000 feet) the motorhome had no power below 2,000 RPM. Additionally, the drivers door window failed in the down position while on our drive home. We put about 2,000 miles on it at that time.

Having an extended warranty and knowing the door window regulator was a International Factory part, i took it to the closest International truck dealer to our house (About 30 miles one way). We had no check engine lights , it was just low power below 2,000 RPM and the drivers door window.

The dealership, Cal Pacific Trucks in Rancho Bernardo, has been fantastic to work with and very helpful while dealing with the extended warranty company.

They diagnosed that even with no check engine lights, the ECM (Electronic Control Module (Main Engine Computer)) was corrupted. What caused the corruption? We did not know. Maybe it was an aftermarket component on it prior to us purchasing it? Anyhow, the extended warranty company would only pay for a reman ECU and this is where things got a bit strange. The ECM remanufacture company wanted to sell us a ECM for a VT365 engine, but the international dealer, via a VIN look up, stated that the ECM for my specific engine/chassis uses the ECM for the T444E (7.3L Diesel) instead of the VT365 (6.0L diesel). I believe that this was due to the normal engine power specs for the VT365 (Used in school buses and box trucks) is different that the power specs VT365 used on the SuperNova. The SuperNova has more horsepower and slightly less torque than the School Bus ratings.

After the ECM problem was fixed, it also turned out that the Variable Geometry Turbo (VGT) was carbon fouled and it was not functioning below properly below 2,000 RPM. Maybe the previous owner let it idle for long long periods (Not good for a VGT turbo). After the turbo was replaced with a new unit, the SuperNova is much better to drive with the real power pull starting just below 1,500 RPM. While that is only 500 RPM difference, with a redline of only 3,200 RPM and the engine screams at 2,800 RPM it has made a big difference in the driving of the SuperNova.

Based upon my experience, with the low volume of production for the International chassis SuperNova, the information available is not as easy to find as other powertrains, but working with an International Truck Dealer has been the best choice.

Additionally, they did state that the later year VT365 engine was reliable (vs the 6.0 Ford (that is based upon the VT365) or the early VT365s and that 6.0 Ford parts for the most part will not help the engine. They said keep it stock. For me, I am OK not having the most powerful engine as long as it is reliable. As you know, breaking down in a motorhome is an awful experience.

Once again, Cal Pacific Trucks in San Diego (Rancho Bernardo) has been fantastic to work with and I highly endorse them for those based local to me to use.

Hope this info helps. looking forward to hearing moreabout your situation.

 

[RVL1161077]

Mine is a 2008 SN with an V365 and 61,000 miles. Had a problem with fuse connection in battery compartment around 45,000. After correcting that I have had to it one more time. Appears the fuse hold get hot a will fail. It's a easy fix but it does happen. No other issues.

 

[Madkel]

Good Morning,
do not mean to hijack this thread, but such good information about a "Fuse holder" in the battery compartment.
I don't think mine has that item. can you clarify if it in the chassis battery compartment or the coach battery compartment?
any pictures would help.

also, I just replaced my 2 chassis batteries with new ones and it has made a huge difference on starting and smooth running right away. I think having good fresh and strong batteries makes a difference too.

 

[RVL1161077]

Good Morning,
do not mean to hijack this thread, but such good information about a "Fuse holder" in the battery compartment.
I don't think mine has that item. can you clarify if it in the chassis battery compartment or the coach battery compartment?
any pictures would help.

also, I just replaced my 2 chassis batteries with new ones and it has made a huge difference on starting and smooth running right away. I think having good fresh and strong batteries makes a difference too.Enginr

 

[RVL1161077]

Engine batteries

 

[Rvguy]

Greetings,
Please share more details about what issues exactly you are experiencing. That would help.

In the meantime, let me share our experiences...
My Wife and I purchased a 2008 SuperNova 6400 in February of 2024. We too love the layout and the strength of the International Chassis. It has about 46,000 miles on it and it has never left us stranded.
It is not a powerhouse, hills are slow (About 35 to 45 MPH) but on the flats it will do 65 MPH which i find to be a comfortable pace.

We purchased it in Salt Lake City and drove it home in 2 days to the San Diego California area where we live.

However, after a trip to Arizona and Carson City Nevada towing about 3500 lbs, i noticed that at elevation (Above 4,000 feet) the motorhome had no power below 2,000 RPM. Additionally, the drivers door window failed in the down position while on our drive home. We put about 2,000 miles on it at that time.

Having an extended warranty and knowing the door window regulator was a International Factory part, i took it to the closest International truck dealer to our house (About 30 miles one way). We had no check engine lights , it was just low power below 2,000 RPM and the drivers door window.

The dealership, Cal Pacific Trucks in Rancho Bernardo, has been fantastic to work with and very helpful while dealing with the extended warranty company.

They diagnosed that even with no check engine lights, the ECM (Electronic Control Module (Main Engine Computer)) was corrupted. What caused the corruption? We did not know. Maybe it was an aftermarket component on it prior to us purchasing it? Anyhow, the extended warranty company would only pay for a reman ECU and this is where things got a bit strange. The ECM remanufacture company wanted to sell us a ECM for a VT365 engine, but the international dealer, via a VIN look up, stated that the ECM for my specific engine/chassis uses the ECM for the T444E (7.3L Diesel) instead of the VT365 (6.0L diesel). I believe that this was due to the normal engine power specs for the VT365 (Used in school buses and box trucks) is different that the power specs VT365 used on the SuperNova. The SuperNova has more horsepower and slightly less torque than the School Bus ratings.

After the ECM problem was fixed, it also turned out that the Variable Geometry Turbo (VGT) was carbon fouled and it was not functioning below properly below 2,000 RPM. Maybe the previous owner let it idle for long long periods (Not good for a VGT turbo). After the turbo was replaced with a new unit, the SuperNova is much better to drive with the real power pull starting just below 1,500 RPM. While that is only 500 RPM difference, with a redline of only 3,200 RPM and the engine screams at 2,800 RPM it has made a big difference in the driving of the SuperNova.

Based upon my experience, with the low volume of production for the International chassis SuperNova, the information available is not as easy to find as other powertrains, but working with an International Truck Dealer has been the best choice.

Additionally, they did state that the later year VT365 engine was reliable (vs the 6.0 Ford (that is based upon the VT365) or the early VT365s and that 6.0 Ford parts for the most part will not help the engine. They said keep it stock. For me, I am OK not having the most powerful engine as long as it is reliable. As you know, breaking down in a motorhome is an awful experience.

Once again, Cal Pacific Trucks in San Diego (Rancho Bernardo) has been fantastic to work with and I highly endorse them for those based local to me to use.

Hope this info helps. looking forward to hearing moreabout your situation.

Hello, I'm glad you had a great experience with that dealership. I actually was there a few years ago before we moved to Texas
I have a 2008 4200 vt365. Had a few issues with the motorhome when I first bought it. I'll list them shortly. However. The first issue I had when I took it to that dealership was my hcu. Brake module. They replaced it. Fixed my engine light. Brake light. Pressure warning ect. I also had a bunch of inactive injector codes all over. I asked them to take a look. They said no issues ( mind you. They didnt even look into it) we moved to Texas. Luckily no issues on the way out here. We get here and the motorhome. Loses all power. No power to the pedal. Engine start fien. Just zero power and won't move. Long story short. Those inactive codes I mentioned were my ecm and idm going bad. I went with an aftermarket pair from go ecm.(1k for both units. Dealership wanted 12k) Fixed that problem. All codes went away and motorhome is running perfect for 3 years now. What I'm trying to get at, you may had. Good tech work on your unit. But the service there sucks. And most techs don't pay attention to detail. They just read codes and don't diagnose or think out side the box to trouble shoot.

 

[Madkel]

Sorry you had a bad experience.

Most of the repair industry (Automotive, Appliances, etc) are plagued by the same issues that you expressed.

Cal Pacific does all of the repairs for the Cal Fire trucks and the US Navy fire vehicles used in Southern California.

I hope you have a better experience at the facilities you choose.

Take care.