My research indicates that the factory stock ones are the most reliable and when they do fail, they fail in the open position most of the time. MotoRad makes a colder one that is well thought of for the Gen IV motors, It is written that Lingenfelter sells these as their 174 degree for the Gen IV 5.3s.

 

"most of the time" doesn't sound too promising... and 174 degrees is way too cool for my engine which is stock

I may have to remove the t-stat from it's housing and use an inline housing in the radiator hose that I got from Jegs

 

"too cool" and "engine" don't belong in the same sentence haha

 

Actually, for an engine to function efficiently, it needs to be within a certain temperature range

Otherwise it's not burning the air / fuel mixture properly

 

Well of course but it is pretty uncommon to reach that point. I guess maybe not if you live in the North and sub zero all the time.

 

I'm not around dozens of LSs everyday. Having said that, I've not had one fail in the closed position, ever. Neither has my other GM vehicles that use this design for the past 19 years. Had one fail, it failed open.

Stock thermostat is called a 187, that's when it begins to open. I thought the 174 was a nice compromise to the old hot rodding standard 160 that we used thirty plus years ago. My old hot rods benefitted greatly from the 160s but was not sure the cooling system in my truck was up for that, hence the compromise of one just a little bit cooler than stock.

 

I have a brand new OE t-stat for my vehicle's 5.3L engine... and it does not have the mechanism built in to make it fail in the open position that the MotoRad t-stat has

I used MotoRad on my old Checy S-10 I used to have when I was tinking with getting electric fans to work right and the truck over heated a few times and the MotoRad t-stat's fail safe mechanism never failed and always worked perfectly.

So, I'll just remove the t-stat from the housing on m,y LS engine and install an aftermarket housing on the rad hose so I can use the MotoRad t-stat so I KNOW my engine will be protected.

 

do you work for motorad??? Sure looks like a hard sale. Just sayin

 

uh no, I do not work for motorad - but I have used their products for years and have protected my engines with them

If you know of another manufacturer that makes fail safe t-stats, please share as I'd be happy to see what they have to offer.

I'm just not a big fan olf the possibility of having a t-stat stick in the close position and see my engine get fried.
(I spent 17 years in auto repair business and have seen this numerous times over the years)

I'm sure those that like to take care of their stuiff to avoid un-necessary repairs understand

 

Installed a Lingenfelter 174F. Don't know if they shipped the wrong one, but it didn't change a thing (going off OBDII live readings, not the factory dummy "gauge").