Coolant temp fluctuations?

[Mr.Sandman]

It's typical for coolant temperature to fluctuate once every 30 minutes. However, if it fluctuates twice or more within 5-10 minutes, that's not normal. If this occurs within the 5-10 minute interval more than twice, there's a 95% chance that the thermostat is faulty.

You can see here the thermostat when I removed it.
Thread 'Coolant temp fluctuations'
https://www.ram-trx.com/threads/coolant-temp-fluctuations.21514/

 

[Grey03svt]

I am having this issue with mine. Shoots up to 218 then down to 188 back up to 215 down to 190...and just keeps repeating that pattern. Started Saturday for about a 30 minute drive, no hot rodding it and was in auto. Did it yesterday with a 20 minute drive too.

Took a few pics of the drastic changes:
View attachment 113970

View attachment 113971
View attachment 113972
View attachment 113973

@Mr.Sandman this is mine doing the fluctuations every 2 minutes. The graph is for 120 seconds.

I figured there has to be something wrong. This happens my entire drive. Whether it's 15 minutes or 3 hours. Constantly up and down

 

[Engine45]

Sandman what t-stat did you get to replace the bad one ?

 

[Mr.Sandman]

Sandman what t-stat did you get to replace the bad one ?

i replaced it with another OEM one, i believe its 195.

 

[Mr.Sandman]

@Mr.Sandman this is mine doing the fluctuations every 2 minutes. The graph is for 120 seconds.

I figured there has to be something wrong. This happens my entire drive. Whether it's 15 minutes or 3 hours. Constantly up and down

Replacing the thermostat is straightforward and inexpensive. It's important to do it promptly to avoid costly repairs that overheating could lead to.

 

[Grey03svt]

Replacing the thermostat is straightforward and inexpensive. It's important to do it promptly to avoid costly repairs that overheating could lead to.

Definitely. Going to get one asap, and probably do a new housing for shits n giggles. Thank you sir

 

[Fifty]

I want to get a new housing, one that has a smoother turn.
For absolutely no reason at all.

Also now that it’s warmer I started watching that logging screen.

Mine does that same step up, and down… but at a much smaller rate. So 195-205

I was also thinking, driving style, traffic, temperature will all effect mine vs yours vs theirs.

 

[Engine45]

I ordered this neck . Price is cheaper than ripa Looks about the same too

 

[Grey03svt]

I ordered this neck . Price is cheaper than ripa Looks about the same too View attachment 128727

Sweet thanks, I'll check this out. What tstat you put in? OEM or a 192? Looking for part numbers for both

 

[Engine45]

I’m still under warranty. And I’m taking my truck in to the dealer on the 1st. I’m gonna ask if they have 192* stats in stock and see if they will put it in. If not. I’ll get an oem part number for one and keep it. The neck will take a lil while to get delivered. I just need my temps normal and the idiot cel off my dash asap.

 

[FULLTHROTTLERICK]

@Mr.Sandman this is mine doing the fluctuations every 2 minutes. The graph is for 120 seconds.

I figured there has to be something wrong. This happens my entire drive. Whether it's 15 minutes or 3 hours. Constantly up and down

Is yours doing this? Mine fluctuates like waves rolling in

 

[Grey03svt]

Is yours doing this? Mine fluctuates like waves rolling in

View attachment 128737

Yes but mine goes up to 218 then back down to 188. Longer waves

 

[DMR]

I ordered this neck . Price is cheaper than ripa Looks about the same too View attachment 128727

I just installed one, looks good and bolts right up.

 

[FULLTHROTTLERICK]

Yes but mine goes up to 218 then back down to 188. Longer waves
View attachment 128739

And do we know for sure that this is abnormal are we just thinking about doing a thermostat swap as a precautionary measure?

 

[Fifty]

Yes but mine goes up to 218 then back down to 188. Longer waves
View attachment 128739

Mine are smaller waves. Much smaller