Skip to main content

Site Navigation

Your Account

Choose Language


Original post by: Darrell ,


For a year I had oil samples coming back with sodium and magnesium readings but no glycol in readings and was flagged as abnormal.

I had the truck checked out and the shop could not find the reason for the loss of coolant...I was adding a quart every 2000 miles.

this is on a 2006 Volvo.

Volvo corporate said it might be flaking of metal in the air charger cooler to explain the sodium and magnesium readings....I will have that checked for leaks.

At the same time I had the coolant leak checked out I had the injectors removed and inspected then changed the o-rings on all injectors. I also had the overhead done.

I went from mineral 10-40 Mobil delvac to Mobile delvac 5W-40 1 ESP synthetic.

My last sample after 16,000 miles came back normal, no traces of any of the previous readings. I had to add 1 gallon of synthetic make up oil in 16,000 miles on an engine that has 614,000 miles....Volvo D12. Even when I was the previous mineral oil, I never had to put make up oil, the only oil I added was when I changed the spin on filters...but I was getting over 60,000 on oil changes with mineral. I run a Harvard by pass system.

The guy at the oil analysis said he thought the readings were from the additive package in the previous mineral oil I was using.

I know the missing coolant is not in the engine or extremities of the engine i.e. compressor, tranny, oil I'm not concerned.

But I still have a coolant getting low problem.

So the shop thinks it is maybe the tank on the radiator might be faulty.

I did something on my own to see why the overflow tank on my radiator never had coolant in it, one side is overflow and the other is where you add coolant. I noticed that I had pressure on the radiator (I think too much) so I left the cap very slightly loose and I went over 3000 miles without adding coolant.

now my over flow side has coolant in it and it acts like it should....when I am running it goes there, then when I stop it goes back to the other side.

any comments would be appreciated