Community Forums

dp7 · 10-14-2021, 12:26 AM

As I approach the five year mark on my coach, I thought it was a good time to check the nitrite free, OAT coolant maintenance requirements. I know this is the Freightliner factory installed coolant because of the label adjacent to the radiator.

Definitive maintenance information is rather elusive & conflicting. The Freightliner annual maintenance sheets only specify a coolant freeze point check each year. The Freightliner maintenance manual shows an OAT coolant change interval of 600,000 miles, independent of time & refers you to Cummins for details. The Cummins quick reference sheet refers you back to Freightliner.

When I called Freightliner I was told that the maintenance manual was incorrect & that Cummins required the OAT coolant be changed every five years. Called Cummins & was told that is incorrect. The OAT coolant is a lifetime coolant & does not have to be changed until engine rebuild, but must be tested at every oil change (annually).

So I went back & reviewed the shop worksheets for the four previous annual services performed by Freightliner shops. They showed a tested value for freeze point & SCA level. I thought it was odd that they were testing for additive levels since nitrite free OAT coolant does not allow the addition of any coolant additives (SCAs).

The worksheets also listed the test strip used as Fleetguard p/n CC2602. A quick web search for this p/n revealed that it is a three way test strip (molybdate, nitrite & freeze point). I also found numerous other Cummins coolant test kits. The purpose of these other test kits were unclear so I called Cummins for clarification. I was told that the CC2602 test strips were for coolant that required supplemental coolant additives (SCAs) & would not give accurate readings with OAT coolants. I was also told that the correct test kit for OAT coolants is a four way kit (molybdate, nitrite, freeze point & pH) p/n CC8997. So I decided to order the correct test kit & check my OAT coolant. To my surprise the only test kits Cummins sells on their website is CC2718 & CC2602 -- no CC8997.

I do not understand why manufacturers make it so difficult to find the correct maintenance requirements for their equipment. Sending owners on scavenger hunts to find the information is just insane! For those of you with OAT coolants, how are you performing annual testing?

Toribk · 10-14-2021, 05:04 AM

dp7

No, they are not and I think the main reasons is loyality to their suppliers or brand.

Since Freightliner is merely the chassis builder and Cummins is the engine manufacturer, I would be inclined to go with the Fleetguard (Cummins) Compleat OAT Extended Life Coolant recommended by Cummins.

Unless I'm wrong, I do not recall reading any need for annual testing for the OAT product.

Please post if you find that is not correct.

BTW, Freightiner told me that their coolant (level) sensor, made by Kysor, was not compatible with the Fleetguard Compleat OAT, but I have not had any issue with it since switching coolant 3 years ago.

Toribk · 10-14-2021, 05:18 AM

dp7,

I found the Cummins literature (pdf) for the ES Compleat OAT and it does mention annual testing as a "precautionary measure" and makes reference to several test kits.

Guess I will figure out which one to order or call Cummins Customer Service.

vettenuts · 10-14-2021, 06:02 PM

Quote:

Originally Posted by Toribk

dp7

No, they are not and I think the main reasons is loyality to their suppliers or brand.

Since Freightliner is merely the chassis builder and Cummins is the engine manufacturer, I would be inclined to go with the Fleetguard (Cummins) Compleat OAT Extended Life Coolant recommended by Cummins.

Unless I'm wrong, I do not recall reading any need for annual testing for the OAT product.

Please post if you find that is not correct.

BTW, Freightiner told me that their coolant (level) sensor, made by Kysor, was not compatible with the Fleetguard Compleat OAT, but I have not had any issue with it since switching coolant 3 years ago.

I was told the same on the sensor so I installed a new one when I replaced the expansion tank and carry the old one as a spare. Also made a dummy plug with the same resistance as the sensor submerged in coolant. Never tested the dummy plug, but that will be the first thing I try if my sensor gives out as it is easily plugged in without touching the expansion tank from the bathroom engine access.

Toribk · 10-15-2021, 04:05 AM

Vettenuts,

That's a pretty cool idea with the dummy plug to get you out of a bind.

Fortunately, on my 2012, I have access from the outside engine compartment to the backside of the expansion tank which makes it much easier to replace the coolant level sensor.

Cat320 · 10-15-2021, 06:03 PM

The chassis builder is the one who puts in the coolant. Flnr says it requires changing at five years or 100,000 miles, whether ELC or standard ethylene glycol. Yes, sometimes it is extremely difficult to get a straight answer from the engine/chassis/coach builder. When I changed my coolant, I asked all three for the coolant capacity. I got three answers from 24 quarts to 32 gallons.

dp7 · 10-16-2021, 12:01 AM

Quote:

Originally Posted by Cat320

The chassis builder is the one who puts in the coolant. Flnr says it requires changing at five years or 100,000 miles, whether ELC or standard ethylene glycol. Yes, sometimes it is extremely difficult to get a straight answer from the engine/chassis/coach builder. When I changed my coolant, I asked all three for the coolant capacity. I got three answers from 24 quarts to 32 gallons.

The Freightliner 100,000/5 years is for non-OAT coolant. Freightliner specifies OAT coolant as 600,000 miles with no time specified. Freightliner does not specify routine testing but Cummins does.

dp7 · 10-21-2021, 01:07 PM

So no one is using test strips to test their OAT coolant as part of the annual maintenance??

capnqball · 10-21-2021, 11:19 PM

Interesting post. To add to any more confusion, when I checked with FL and Cummins on my '17 Ventana 6.7/360 4 months ago Cummins stated specifically do not use ELC or OAT coolants. Use EG Precharged with SCA's and plan to change every 5 years. I then found Fleetcharge coolant to match that description, purchased from NAPA. I would have preferred Fleet Guard but Cummins Parts were out of stock and didn't know when it would come back in stock.

dp7 · 10-22-2021, 12:18 AM

Quote:

Originally Posted by capnqball

Interesting post. To add to any more confusion, when I checked with FL and Cummins on my '17 Ventana 6.7/360 4 months ago Cummins stated specifically do not use ELC or OAT coolants. Use EG Precharged with SCA's and plan to change every 5 years. I then found Fleetcharge coolant to match that description, purchased from NAPA. I would have preferred Fleet Guard but Cummins Parts were out of stock and didn't know when it would come back in stock.

I think you got some bad info from FL or your chassis was built before they switched to OAT. I have the same engine and same year coach, & the label shown below is posted next to the radiator. Do you not have this label? Cummins documentation also references OAT.

fagnaml · 10-22-2021, 03:25 PM

I agree with the statement that "Freightliner and Cummins are not on the same page". Per Cummins, a good quality extended life coolant is acceptable for my 6.7L ISB engine. However, for some reason Freightliner chose to design the coolant system for my XCR chassis to only use "purple" Heavy Duty SCA Charged coolant (and then periodically check SCA levels). I asked Freightliner about switching to an extended life coolant and the response was my current coolant level probe would not work properly for "red" coolant and that I need to continue using the "purple" HD coolant. So, I keep a gallon of Prestone Command Purple HD coolant in a storage compartment should I ever need to "top off" the coolant receiver tank --> https://www.walmart.com/ip/PRESTONE-...b22d30b4f975c6

vettenuts · 10-22-2021, 07:04 PM

Quote:

Originally Posted by fagnaml

I agree with the statement that "Freightliner and Cummins are not on the same page". Per Cummins, a good quality extended life coolant is acceptable for my 6.7L ISB engine. However, for some reason Freightliner chose to design the coolant system for my XCR chassis to only use "purple" Heavy Duty SCA Charged coolant (and then periodically check SCA levels). I asked Freightliner about switching to an extended life coolant and the response was my current coolant level probe would not work properly for "red" coolant and that I need to continue using the "purple" HD coolant. So, I keep a gallon of Prestone Command Purple HD coolant in a storage compartment should I ever need to "top off" the coolant receiver tank --> https://www.walmart.com/ip/PRESTONE-...b22d30b4f975c6

I went the other way, I switched to the OAT coolant and carry a spare sensor based on what Freightliner said. Additionally, I know a number of guys that switched over and have never had a coolant sensor issue.

ArtJoyce · 10-22-2021, 08:23 PM

Manufactures started using Oats antifreeze 20+ years ago. It was environmentally friendly. They put the label on so you would not mix it. Mixing it can cause the coolant to gel and large maintenance cost.

SCA levels are required in diesel engines so you don't get cavitation of the coolant and erosion of the coolant passages. You should test every year and SCA if needed.

capnqball · 10-23-2021, 12:27 AM

Quote:

Originally Posted by dp7

I think you got some bad info from FL or your chassis was built before they switched to OAT. I have the same engine and same year coach, & the label shown below is posted next to the radiator. Do you not have this label? Cummins documentation also references OAT.

No that is not the same tag that is provided on my '17 Ventana. My chassis is a '16 year unit. Coach was delivered in Dec. 2016. Interesting change in stated coolant types which I will pursue with Cummins to get further confirmation.