Another Cooling System Question

[xford]

I recently had my 2006 LS V8 w/ 155k miles overheat going up/over a long grade. The overheating situation wasn't too extreme and was able to bring temp down by turning off the AC. As a result of the problem Ive been checking via Live OBDII Scanner with ambient outside temperatures of 80-85F I'm seeing 205-209F around town and 212F to 215F at freeway speeds of 70-80mph. Up a 15% grade of 2 miles near my home temp ranges from 219-224F and fan goes on high until leveling off. The entire cooling system has been replaced a couple of times over the years & currently the majority of parts are Motorcraft including degas and hoses. Notable exceptions are a newer Spectra Radiator and Gates Thermostat housing assembly (maybe 2yrs?). About a year ago the tube behind the intake manifold was replaced. The system appears to be properly pressurizing and the water pump, fan, and recirculating pump are original. The proper Motorcraft Gold coolant was changed in the last year. Thoughts as what the most likely culprit is vs. going all w/ all new parts?

 

[joegr]

It's the Gates housing. It does not allow enough flow. You need the Motorcraft housing, crossover, elbow, and thermostat.

 

[xford]

It's the Gates housing. It does not allow enough flow. You need the Motorcraft housing, crossover, elbow, and thermostat.

Thanks as always Joe! I'll replace with Motorcraft and update.

 

[04_Sport_LS]

The Spectra radiator could be suspect too. If the tube size and tube count isn't to the same spec as OEM.

"Meets or exceeds OEM specifications" can be very misleading when it comes to aftermarket parts.

Start with the aftermarket t-stat housing as Joe suggested. That is a known issue.

 

[xford]

Replaced the entire thermostat assembly with Motorcraft and updated water pump at the same time. Unfortunately no change... Have a Motorcraft Radiator on order.

 

[ajv8]

224 is far from overheating, 245 is when you need to flip the key and pull over

ideally you want it to max out at 220 under any condition, your radiator might be a little underperforming

 

[milehighmikey]

Also make sure that there is nothing blocking the radiator sandwiched between the radiator and the condenser.

 

[04_Sport_LS]

By general consensus on this forum... on hot summer days the actual max operating temp seems to be 230 F. At least on the V8... measured at some of the smaller hoses on top of the engine.

 

[xford]

224 is far from overheating, 245 is when you need to flip the key and pull over

ideally you want it to max out at 220 under any condition, your radiator might be a little underperforming

Agree but since it recently overheated - dummy gauge to full tilt - something is not right... Hopefully its the radiator

Also make sure that there is nothing blocking the radiator sandwiched between the radiator and the condenser.

Yes was checked post overheating and prior to most recent parts replacement - nothing excessive other than the typical minor road related debris

By general consensus on this forum... on hot summer days the actual max operating temp seems to be 230 F. At least on the V8... measured at some of the smaller hoses on top of the engine.

230 seems excessively hot to me...where is the OBDII reader picking up the engine temp?

 

[joegr]

...230 seems excessively hot to me...where is the OBDII reader is picking up the engine temp?

From the CHT (cylinder head temperature) sensor.

 

[04_Sport_LS]

From the CHT (cylinder head temperature) sensor.

Which is between cyls 3 & 4... under the intake manifold. You can see it if you look hard enough.

It can't be pulled without removing the intake.

 

[04_Sport_LS]

I've always seen 230 most everywhere around the engine... checking with an infrared temp gun.

 

[smegun]

Replaced the entire thermostat assembly with Motorcraft and updated water pump at the same time. Unfortunately no change... Have a Motorcraft Radiator on order.

my 2002 gen one in process had to think when bypassing the heater core it ran without the dual climate control valve im not as lucky currently with it ....i flushed system with no abnormal sights but i have had problems with another vehicle a radiator that when flushing with a solvent destroyed the glues holding the plastic tanks to the rest of the core so my advise is plain jane h20 flushing and im going to try global or the the motorcraft gold fluids although you look at it the preston now touts any radiator fluid replacement eco friendly waves

 

[xford]

Appears a new Motorcraft Radiator has resolved the issue. Temps via the OBDII Live Scan are now down 3-5 degrees across various operating conditions. Max I have seen thus far pulling a long steep grade is 221 at 92 outside temp. Therefore, I would not recommend Spectra as an OEM replacement radiator. Have a road trip next week to Arizona which will definitely give the full cooling system a test with daytime temps in the 100-110 degree range! I'll let everyone know how it goes and thanks for the assist.

 

[04_Sport_LS]

Once again a case of aftermarket junk NOT meeting or exceeding OEM specifications.

 

[tireman]

I've had no issues with aftermarket parts. What I do have an issue with is the junk they built this car with LOL!

 

[joegr]

I've had no issues with aftermarket parts. What I do have an issue with is the junk they built this car with LOL!

And yet, it's still going.
I never found any aftermarket part that was better than the factory part. The best that I did was "about as good", and that was rare. (I actually did okay with aftermarket radiators.)

 

[04_Sport_LS]

I've had no issues with aftermarket parts. What I do have an issue with is the junk they built this car with LOL!

Wait until you start having to change suspension parts. The aftermarket contol arms, steering knuckles, and shocks... only hold up for about a year.

 

[smegun]

Wait until you start having to change suspension parts. The aftermarket contol arms, steering knuckles, and shocks... only hold up for about a yea

 

[smegun]

probably should press fit some energy suspension bushings rather than buy the control arms complete although there getting better but doubtful better than vulcanized real rubber or original .... e worst is letting it rust out use some jasco rust and primer under there and replace with at least grade 8 bolts ... i went to the trouble of doing the radius arm bushing on my truck but used duralast about a week

 

[04_Sport_LS]

Good luck with that. The factory bushings are swage fitted... and a total pain to get out.

Pressing in new bushings is a pain in the butt. Too much can go wrong.

 

[xford]

Back from AZ with zero issues. Outside temps were cooler than expected in the 90-100 degree range due to seasonal monsoons so the cooling system did not get the full test I was expecting. OBDII live readings were great mostly in the 205F to 212F range w/ over 700 freeway miles traveled.

 

[04_Sport_LS]

Yay!!!