engine temp

[Havasubum]

ive got a buddy who just picked a 96 suburban with the 454 and was wandering what temp the engine is supposed to be at? anyone have a similar vehicle that can chime in

[curtis73]

In the middle. That's not a joke. Most of those came through with a "dummy gauge". It says cold when its cold, pegs hot when its too hot, and defaults to the middle when its between 150 and 220
If its truly a sweep gauge, its still not accurate at all. It should show somewhere between the orange band at cold and the orange band at hot.
Beg borrow or steal an IR thermometer, or install a mechanical thermometer in the thermostat neck. I think you'll find that the factory gauge is only a representation at best. I have a 160 stat in a 96 but the gauge reads 120. I've verified actual temp with a laser/IR thermometer on the 'stat neck and its getting up to temp, but the gauge is just way off.

[Havasubum]

he said that the gauge is a the middle (210) and will go up to 3/4 of the guage. just wondering if it was normal.

[victorfb]

210 - 220 is pretty normal for the vortec 454s. any higher id say you better start looking for the problem. GM ran the engine oil through the radiater as an oil cooler aswell as the transmission lines. bypassing the transmission line from the radiater and installing a large external trans cooler in front of the radiater normally helps quite a bit to help keep temps down. installing an aftermarket trans temp guage is a big plus. id put the trans temp guage on no matter what. a worn transmission will create alot of heat and if it is running through the radiater it will then heat the engine higher than normal aswell. so definatly keep and eye on the trans and have it checked. a trans shop can pull the pan and see how much contamination is running through it which causes the heat. if this was a 91 or 92 id say you were in trouble as those years had a problem of running too hot and with the non programable ECU, no matter what you did the ECU would change timing, air fuel, ect, to keep the temps high for what GM says is better for emissions. once the vortec engine was installed and the differant ECUs the temps werent a problem. since you say the factory guage is running up to 3/4 id say there is a problem unless it only does this while towing heavy loads.
is the burb 2 or 4 wheel drive? 1500 or 2500?

[Havasubum]

its a 2500 4wd only goes past half in the city but not on the highway. haven't pulled a trailer yet with it

[Beer-30]

It would have a normal 195* thermostat, so reading close to the 210 mark would be fairly normal. One must stick a thermometer in the fillerneck of the rad after driving around to see the actual temp.
Then, you have to consider WHERE the gauge sender is reading from (cyl head? block? intake?) as these can be a few degrees different.
THEN, you have to take into consideration the difference from gauge to gauge as well as wear and tear. The original gauge in a '96 has swung many many times and will not be as accurate as when new. Same for the sender. To boot, some gauges will read 205 when sensing 195. Some will read 185 when sensing 195. ETC.

[Beer-30]

3/4 gauge is not good.
Mine is a '98 Vortec 454, and at this stage of the game, it has never gone past 210. In Havasu, idling with the A/C on full, it sits at a gas station at 210 on the mark. I have not done a thermostat or radiator on it YET, but we'll see this summer. At 9 (mine) years old, I would expect the rad to have a significant pile of crap in the lower portion. Plus, the therm will only open and close so many times.
If you are going to be pulling with it, in the summer, I would stick in a new rad (Delco is around $250), a new water pump ($140?), and a new therm ($10?). Just to be safe. Another thing I always replace when doing that same amount of cooling equipment is the fan clutch ($40). I would stick with AC/Delco parts. If my original (AC/Delco) went 9 years, I would want the same part again.

[victorfb]

Then, you have to consider WHERE the gauge sender is reading from (cyl head? block? intake?) as these can be a few degrees different.
.
the sender is located in the side of the head just above # 3 and 5 cylinders.
it does sound like he has a definate problem. wether it is a radiater going south, a trans going south, or even as you mentioned a bad clutch fan, water pump, thermostat, ect. in any case he really needs to track it down before he starts towing for sure.
if interested i have a few items you may want to consider. had a custom 6 core radiater made for my 91 GMC 4x4 dually that i am no longer useing. actually i am parting the truck out. i did everything imaginable to try and help keep the temps down untill i learned about the damn ECU making it impossible on that year. the 6 core radiater was built without the provisions for the oil cooler since i installed an external cooler in front of the radiater. have that aswell. but a new side tub can be soldered on if you want the oil cooler lines to go through it. a heavy duty fan clutch with 6 blade fan reverse rotation. and if you need any running gear stuff, the front and rear end had 4.56 gears installed. the 4L80E trans was bought brand new from GM (5k miles). transfer case never opened, but rarely used. if you need anything for that subi, just let me know.