Dr.Dizzle, does the Peak DC meet the HOAT qualifications? I'm not sure what the "H - hybrid" part means. I did read your response re: the 4 HOATs, but I was wondering if this formulation of Peak DC also meets HOAT.

 

The Peak products are (OAT) organic additive technology formulations. They are based on fully (neutralized acid) corrosion inhibitors. One requires the use of SCA/filters while the other requires an extender product, which are bottled addatives or inhibitor packages. The Peak products do not qualify as HOAT formulated coolants.

Hybrid coolant technology is a blend of (OAT) organic additive formulation and an (IAT) inorganic additive formulation. The addition of the inorganics such as salts, silicates, borates etc.. make a hybrid coolant.

 

Dr.Dizzle, Thank you.

 

I know this is an old thread but it was very useful, thanks AH.
One thing I did that helped was to remove the thermostat from the rubber O ring and just install the O ring, no leaks. I did my change in 30 degree weather also so there was no way the thermostat was going to open.
Also something I found, it was taking too long for the antifreeze to drain form the overflow tank so what I did was take a piece of rubber and a plastic cap and drill a small hole in both and place them over the opening of the overflow tank (rubber then plastic cap) and using my air compressor and rubber tipped blower I then VERY CAREFULLY injected air in to the tank. The system should have no more than 15LB of pressure so short blasts worked well. Cut the time it takes to drain the tank in half.

Hope this helps someone

 

I plan to drain the coolant, take the t-stat out and refill with 20/80, Ryd Lyme/water. Then put cardboard over part of the radiator and go run the snot out of it for at least 20 minutes and let the Ryd Lyme do it's thing. Ryd Lyme is a biodegradable industrial descaler and it's safe for all materials. Then flush with tap water til the TDS of the water out = the TDS of the water in. Then drain that water and do the final fill with HOAT/distilled water. Maybe 1/3 HOAT/2/3 water with an extra bottle of additve in this climate. Craig

 

Don't you defeat the purpose of a de-scaler by flushing with tap water? You won't get all the tap water out.

Minimum coolant allowed is 44%, so add enough coolant to make 44% and then top off with distilled water.

 

I'd have to read the directions that come with rydlyme but I think it's better to get the old mixture out first. I've cleaned up some really scaled up cooling towers with it so I doubt if my 32 grain tap water would have enough hardness to reduce it's effectiveness very much. There's lots of other descalers but I've used rydlyme the most and I know how well it works. I've cleaned up completely plugged industrial closed loops with it before. It's also environmentally safe. I've kept up on my cooling system maintenance (coolant changes and DCA+) and it might be overkill to do a complete descaling but that's just me. I didn't put this in my previous post but I've always done a distilled water rinse before the final fill. I've talked to the Fleetguard people about running a lower % of glycol and using more DCA+ to keep the additives up to where they want them and they said, go for it. My thinking is to only have the freeze protection I need for my climate and have the most thermal efficiency for this stinkin hot desert. It wouldn't be the first time I've been wrong. I'm open for better ideas! I know it's another subject but I've been searching for a finer micron hot water filter than what automotive coolant filters are - 20-40. I've cured some really bad electrolysis pitting and sandblasting problems in industrial water and closed loop systems and my experience has been, 5 mic is entry level - 1 micron is awesome. I've used a 1 mic whole house filter for 15 yrs and 3 houses and it's scary to see what's in our drinking water! Craig

 

I didn't think HOAT used DCA additives, so adding them is like mixing HOAT with non-HOAT.

 

That, I don't know. I use Fleetguard ES Complete blue, on Cummins recommendation. Then I buy the test strips and a bottle of DCA+ every year or two to keep the nitrite and molybdate in the recommended range for O2 scavenging and passivation. The DCA+ is the additive match for the ES Complete blue. They have other glycol/additive combos but I know nothing about them. The additive also keeps the Ph up to keep the hoses from getting hard and rotten. The Fleetguard people say this engine doesn't need such high levels but I do it for the hoses. Craig

 

Gotcha, that's not a HOAT coolant.

There are issues with HOAT not playing nice with non-HOAT coolants, but at this point you would know.

 

I found a jug of it in the garage and it doesn't say. It's ext. life, low silicate, meets all the big mfgr requirements and compatable with all other antifreezes. The back of the jug says it never has to be changed if the additives are kept up and it's not contaminated but the FG customer service people don't recommend going over 5 yrs. I was wrong on the additve name... it's DCA4, not DCA+. Craig

 

I'm just over 100,000 miles on an '05 3500 that I bought used, and would like to service the coolant with the quick "drain and refill" method every 2 years as mentioned in this thread. Is there any way to tell if my coolant is HOAT or not so that I don't mix the two?

Thanks,

Troy

 

It should be HOAT as that was the OEM fill. If you don't know do a complete flush as listed above and then add HOAT and do the 2 year drain/fill.

There are lots of other coolants than HOAT, but HOAT is good and lasts a long time. I would rather run something like Cat ELC-1, but the way HOAT doesn't play with others kept me using HOAT.

 

Just switch to Chevron Delo Elc. It mixes with everything there is. Plus its a lifetime coolant. You never need to change it.

 

I've done extensive research on the coolant formulations and the many products offered. I have found that the Chevron Delo ELC coolant is an ethylene glycol based formula and contains Chevron`s patented carboxylate technology and deionized water. This product does not contain conventional inhibitors like silicates, nitrates or amines. Coolants that contain carboxylate technology are recognized as OAT formulations(Organic Acid Technology). OAT formulas contain no silicates for corrosion protection;whereas, the Hybrid OAT or HOAT type coolants specified for our trucks contain a small amount of silicates in the formula,but not enough to fall out of solution. Keep in mind if the product says "NO Silicate" it is not a G-05 HOAT formula.

The Delo Extended Life Coolant/Antifreeze does not meet Chrysler MS 9769 specification and manufacturers’ requirement as per their data sheet. The specifications mention that the Delo ELC is recommended for all "heavy duty" cooling systems including Cummins; however, suggesting that this product is marketed for over the road semi trucks and earthmoving equipment engines. This makes no mention of light duty manufacturer specs. This is a very robust coolant, but HOAT coolants do not play well with other formulations as AH64ID mentioned.