All of the other coolant threads seemed to be a few years old, sorry if this issue has already been dealt with.

Basically, coolant is low in the reservoir in my 2004 G35 and I wanted to know if there was anyone who could recommend any particular over the counter brand instead of going to the Nissan dealership? I haven't had any issues (no leaking, A/C works fine, etc) but it's about to be getting warm so I wanted to fill up the reservoir. My autozone has the Peak 50/50 mix that says it can be used with any color coolant (the G35 currently has green coolant) and it says silicone and phosphate free. Has anyone used Peak before, or should I just stick with Prestone, or just go ahead and take it into the dealership so they can fill it up with their coolant?

[Edited on May 22, 2011 at 12:11 PM. Reason : asdfsa]

5/22/2011 12:09:09 PM

Either is ok. 50/50 mix is probably the way to go although you would save money buying and mixing your own (use distilled water if you do) but then you'd have tons left over too.

Also coolant is engine coolant which is actually attached to your heater not A/C.

Also the reservoir is an overflow really as long as there is anything in it at all you're in good shape but you might as well check it out.

5/22/2011 12:35:13 PM

Quote :

"My autozone has the Peak 50/50 mix that says it can be used with any color coolant (the G35 currently has green coolant) and it says silicone and phosphate free."

This is what I use in the wife's Highlander. Toyota has strict requirements about the use of phosphate and silicate-free coolant. Even though it's one of the top rated coolants I'm just not going to pay $30/gal. for the pink stuff from Toyota.

5/22/2011 4:40:47 PM

IMHO I'd say no matter what the label states on the mix-all coolant jugs that you should never mix different colors, to oversimplify it. Yes going by colors seems silly but they are dyed to designate different chemical components and mixing certain different formulas can definitely reduce the potency of the antifreeze or cause precipitants, which can tear up your seals, water pump, or eventually lead to the brown sludge buildup which can severely block your radiator or heater core. For a car you plan on keeping and maintaining it's really worth it to purchase OEM/factory spec to top it off or refill it IF it has the factory coolant in it. Don't forget that the jugs they sell at the dealer are 100% anti-freeze, not the 50/50 coolant/water mix.

When you calc it out you are trying to save 5-10 bucks and risking some repairs that are a lot more expensive for something that should be lasting you a long time. If you're just topping off the reservoir get the gallon jug from the dealer for $20-25, not much more than auto parts stores. One thing to note as mentioned before: if your car's coolant has been completely flushed, say possibly at the last time your water pump was replaced, then use what that mechanic refilled it with and in most cases you can go by the color of the coolant.

5/22/2011 5:38:20 PM

^ Agreed.

I always stick with OE specific coolant if just topping off. Another option if you are really against the OEM coolant is to do a 100% flush and re fill with the basic green stuff.

I have had no problems with the PEAK coolant in my older car. I just fill it with whatever walmart has on sale.

5/23/2011 8:20:06 AM