I bought 2 gallons of 100% Zerex (non pre-mix) from Walmart.

Okay:
-1 bottle empty
-1 bottle full
-mark the fluid level on the full
-pour the full into the empty until the levels are the same
-mark the 50% point on the bottle that already has the 100% mark

Now I have a mixing bottle. I wanted accuracy because of a project I am working on (you can read about it in another thread in this forum).

-fill the mixing bottle with distilled water (also from Walmart)

Now do I have a 50/50 mix? Not according to my freeze point coolant tester. I got -32*C. Can't be right. Off to Canadian Tire - mechanic did the litmus test and said he gets about -32*C.

Now either Zerex is shipping slightly weak concentrations of coolant or someone is pissing in the water.

are you sure you complete emptied the old coolant?
why..if some remained it would dilute the new..hence the lower than expected freeze point..

just a thought.

-dkenny

_________________
84 BB school bus, DD8.2L turbo ->the transmission died..too expensive to fix..it'll be heading to the scrap yard..4/11)..Bus gone to Scarp 8/23/11
06 Liberty CRD
'99 dodge ram 2500 quad cab, 4x4, 24v
all Biodiesel powered when its warm enough

If you're using one of those coolant testers with the floating needle, they are very sensitive to the temperature of the coolant. I did the same 50/50 test with new coolant to calibrate the tester and it read about -44F freeze point at room temp IIRC.

_________________
05CRD: GDE Hot ECU & TCM tunes, Provent, Cat filter, Facet lift pump, TransGo kit, Florida TC, Samcos, stainless brake lines, HDS thermostat, Renegade light bar,
Bilstein adjustables, Al's Gen 4.5 Arms, 235/85-16 Duratracs, DTT rear, Elocker front, EVIC+TPMS, Turbo timer, McNally pillar gauges, Weeks Stage II kit.

also where are you located??

-32C where I live..ah..it'll NEVER HAPPEN!!..The coldest in my 32yrs here is around 5F...
since -40F and -40C are the same your talking warmer..maybe -20F..darn cold for sure..

but what do you expect to see for the lowest temp??

-40C...or less???
I hope you plug in at night or park in warm garage..

-dkenny

_________________
84 BB school bus, DD8.2L turbo ->the transmission died..too expensive to fix..it'll be heading to the scrap yard..4/11)..Bus gone to Scarp 8/23/11
06 Liberty CRD
'99 dodge ram 2500 quad cab, 4x4, 24v
all Biodiesel powered when its warm enough

he headsed to Canadian Tire...it gets cold enough

_________________
2005 Liberty CRD Limited
Light Khaki

The over-all mix (what is now in the truck) is better so I think just one jug was off. I could check the lot numbers tomorrow.

It doesn't get too cold here; I am in a rare part of Canada that gets freezing temperatures for one week around Christmas. Sometimes not. I mostly wanted the mix so that the proper amount of rust/oxidization protectant was used.

I have left over straight Zerex so it is easy to fix.

CATCRD, the local mechanic did check the mix with a test strip getting the same result as my tester.