DEI Radiator Relief Coolant Additive Engine Coolant for Cars, Trucks, RVs, Motorcycles & More Radiator Coolant Reduces Engine Temps Up to 30°F 16 oz.

Simply put, it works. Before adding this additive to my 05 Pontiac GTO, I'd run around 180 on the highway and steadily climb to 200 in slow traffic. This is with an all aluminum radiator, 160 thermostat, and a 30/70 Zerek G-05/distilled water ratio. After adding the DEI additive, I'm around 175 on the highway. However, I've yet to crest 190 while in slow traffic. It climbs from 175 much slower and cools off much quicker once I get moving again.In my opinion, works much better than Water Wetter which I noticed no difference on.

I have a BMW… It’s about 10 years old and like a lot of other BMWs it has cooling issues… I live in LA and usually the summer time is the only time it’s an issue… Lots of idling because of traffic…It’s been hot lately and so I thought I would give this a try because my mechanic has tried a bunch of things and the temp gauge will sometimes “creep up.” I drove it today and it was in the 80s and zero creeping problem ....for the first time in a while (with it being that warm) iEnough said! (I run straight distilled in the summer and this has anti corrosion additives. Set!!

I’ve used on a couple cars and it helped out in summer well…good value good price

fast delivery. Used as specified. Seems to be working as stated

Didn’t see any noticeable change in engine temp.

Dumped this in my Humvee pressurized coolant reservoir and it didn't lower temps at all. It has a hydraulic fan that turns on like clockwork at a specific point in my commute, so even a 5* drop in temp would be noticeable. Zero change after driving for a week. It might be better if I ran just this with distilled water. Also, smells like urine.

Texas heat forced me to try this out. I flushed my system and did a 90/10 mix and the results are great. It keeps my truck running cool no matter how hard I push her.

Traveling in Arizona in 115+ heat, I wanted a little extra cooling capability. When parked with engine running for AC, extra capability is great. It kept engine temp at 197 degrees while idling for 45 minutes in 115 degree air temp.