any advice is good advice

I have a 05 tacoma 4.0 and the running temp stays right under half and if like it to stay a little cooler. Has anyone tried putting red line or royal purple additive to the coolant does it help or is it a, bad idea.. its says it's sapose to keep it 20 degrees cooler

 

What is this word you use " sapose " my young apprentice?

 

That coolant temperature gauge isn't really accurate. It's hard to judge what's to hot or not without knowing what temperature your coolant actually is. Buy a scangauge or ultragauge to find out what your ECT (engine coolant temperature) actually is before you start chucking any snake oil in there.

Also, your thermostat determines what your coolant temperature is at the end of the day. If it's too hot you probably need to check your thermostat, pump, hoses, and radiator for flow rather than add a bunch of additives that won't help parts that are broken.

 

That needle is far from an accurate gauge. Its gets to its normal spot when the coolant is like 160. I've had the coolant to 210 on a hill and it never moves. It usually operates at 188-190.

 

Good to know guys so my next step it radiator I already changed pump and thermostat... thanks again guys.. I love this site... snake oil that's priceless lol

 

Changing all that stuff is not going to affect where the needle sits on the cluster though. Unless you can get the coolant to be around 150, which isn't healthy for the motor. The radiator is going to be a waste of money. The t-stat determines temperature as long as everything else is operating normally.

 

The radiator isn't a waste of money if his is old and getting plugged up. At ten years old most people would at least check to see what the condition of the radiator is like.

The gauge is a dummy gauge, built only to assure people the truck is working. By the time it hits red the damage to your truck has been done long ago.

 

I put Royal Purple in my radiator. As said above, the thermostat controls water temp to a point. When it's fully open (like here in Arizona in the summer) the temp will be a little lower with the RP than without it.

 

Like others have said, there is no telling what your temp really is by looking at the gauge. Ignore the scanguage advise though since spending $150 or more to do nothing but get info out of your ECU with a crappy graphic interface is just flushing money down the toilet. Spend $25 on am ELM32 ODBII bluetooth adapter and then $6 on the Torque app for your phone.

 

Torque works well too but then you need to setup your phone in a holder and keep it charged to have a reading from the bluetooth OBD II sensor. A Scangauge or Ultragauge lets you have something in your truck specifically for monitoring whatever you want from the OBD II. It's personal preference, not money wasted.

 

Opinions are like...

 

Hi all.

I've been running my ScanGuage II for 2 years.
1 - My trucks coolant guage is spot on. Although it doesn't show an actual number, it comes off bottom at 38 C every time and runs near half way at 83 - 86 C
2 - The ScanGuage is an awesome unit. The tranny temp I added is a great indicator of how hard I'm working the truck. The tank to empty is a good thing and the ability to read codes if and when needed will be more than handy.

Cheers
Ray.