Type of anti freeze

[jimbo2013]

I have an 08 or 09 350, what is the recommended type to use?

Anyone have an idea how many gallons

[tom chelbana]

Cummins has numerous engines with 350HP. ISB 6.7, ISC 8.3 and the ISL 8.9 and each has different anti-freeze capacity. Best thing to do would be to contact FL and find what coolant was put in at the factory and the capacity. There are many different coolants there and some owners have had major problems not putting correct coolant. Color isn't enough to say which is the correct coolant for you coach.

[rvbiker45]

I just changed my coolant fluid and this is what the Cummins Service Center in Dallas told me: Drain the system; fill with tap water and run the engine for about :15; drain that water and add Cummins/Fleetguard Restore radiator cleaner, P/N CC2610, mine took about 5 quarts and fill the rest of the system with tap water; run the engine for 1-1.5 hours to get the engine up to normal operating temperature; drain that fluid and refill with tap water; run for about :15 minutes; drain that fluid and then fill with antifreeze/coolant. They recommended Cummins/Fleetguard ES Coolant (extended service). My system took 10 gallons even though the system is rated at 12 gallons. While doing the change out, I replaced the thermostat and the radiator cap. The thermostat is available from Cummins and the radiator cap I got from NAPA. Cummins does not carry the cap. The ES coolant is rated for 1,000,000 miles or life of the engine. They recommended using this type and it is about the same price as the regular type.
This is easy to do, it just take some time. Cummins said they usually take 8 hours to do the job in their shop.
Use caution when draining the fluid as it will be hot. Collect the old antifreeze and flush, dispose of properly. It is very toxic to animals.

[hayward3411]

Use distilled water in your system. I also used distilled water when flushing.

In my ISB 6.7 (2007) I used Global Final Charge, this is a extended coolant.

[jd956jd956]

Yes! Distilled water! Can use regular tap water on initial flush(s), but distilled water is imperative. (Last couple of flushes with distilled water, then 50/50 coolant & distilled water)

[rvbiker45]

I agree, distilled water is probably better. But, in talking with Cummings Service, i asked if I should use distilled or tap and they said tap. So, judging from that exchange, if someone were to take their vehicle to Cummings to have the work done, you would probably get tap water. Just my opinion.
If distilled water is your choice, it would probably be better to do the job yourself.

[mackwrench]

Isn't it kinda of odd the water that's "safe" for us to drink isn't something you'd use in your engine?....

I've heard opinions on this all over the board, I've used both, never had and issue with either.

I think it's a matter of location, some water is hard, some too much iron, some have chemicals that make it safe. Use what allows you to sleep at night.

My .02 on H2O is no matter which water you mix your coolant, make sure your using a quality coolant that meets/exceeds the specs for your engine, at the proper 50% mixture.....if your not using extended life coolant make sure the DCA levels also in spec, using the correct spin on coolant conditioner


FYI, I'm still using the icky green stuff, change my conditioner and check DCA levels annually..... primarily because it's no issue, when time comes and I open coolant system up for whatever reason, I'll change to ES..... maybe, lol

[jd956jd956]

Great info... and, agree MackWrench... The purpose of the distilled water is to avoid the otherwise naturally occurring minerals which can leave deposits in the cooling system. I recently read about the OAT technology (and others) and read some of the 50/50 pre-mixed products use Deionized water which is about as pure as it can be. This thread has encouraged me to soon drain and go with OAT and be done with it And, I have a deionizer that I use to rinse my coach after washing, so I will use it if I do not buy the pre-mixed product.

[LoggedOff]

You definitely want an OAT coolant, and likely one that has a Caterpillar EC1 rating.
Final Charge, Rotella, and Delo are good products. Cummins has lots of whitepapers out on OAT coolant and how it fights cylinder pitting and the benefits. And definitely fill with distilled. If you don't have a cooling problem, just flush it with tap water. Some of these chemicals out there today that clean out cooling systems are pretty harsh on the welds and rubber parts of the cooling system. My system was 10 yrs old when I flushed with Fleetguard Restore and it took 6 months to chase all the pinhole leaks that popped up and must have lost close to $300 in coolant as well over that time

[jimbo2013]

Found out I have Final Charge, so it's good for a long time.

I just did a hydronic water heater in my coach, the manufacturer tech support guy said try your best to use distilled water not tap.

He pointed to minerals in tap that the system is better off without.

[Team G]

Did exactly what rvbiker45 wrote - with DISTILLED h20 for the mineral reasons sited. A bit of a PITA but woorth the effort. The use an OTA (final charge) and you will never regret it, no checking no SCA Just run er'.