C5 getting really warm in traffic.
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,883
Likes: 76
From: Portland OR
C5 getting really warm in traffic.
'01 base M6 with a ton of miles. Been my daily for 4 years now. My new commute hits a little traffic now and my car got wicked hot.
Sitting at a stop a mile from my exit I noticed my temp gauge was at 255. Nowhere to go, I crawled the mile to the exit and just before I jumped, the temp drops to 220. About 210 the whole way home. Check fans, coolant, all looks good. Next morning 40 degrees doing 65 temp goes up to 250, then drops, up, then drops. Get to work, call NAPA, order thermostat and swap it out, complete flush and fill.
Now when I hit traffic it goes up to 235, but that's all. I used the OE 187 temp, I have a 160 on the shelf. 235 is hotter than usual but my commute is different now. Still hotter than I fell comfortable with. Runs cool flogging on the twisties in the woods all day.
So should I go with the 160? Or just plan on a water pump and radiator this summer?
Sitting at a stop a mile from my exit I noticed my temp gauge was at 255. Nowhere to go, I crawled the mile to the exit and just before I jumped, the temp drops to 220. About 210 the whole way home. Check fans, coolant, all looks good. Next morning 40 degrees doing 65 temp goes up to 250, then drops, up, then drops. Get to work, call NAPA, order thermostat and swap it out, complete flush and fill.
Now when I hit traffic it goes up to 235, but that's all. I used the OE 187 temp, I have a 160 on the shelf. 235 is hotter than usual but my commute is different now. Still hotter than I fell comfortable with. Runs cool flogging on the twisties in the woods all day.
So should I go with the 160? Or just plan on a water pump and radiator this summer?
Drifting
Joined: Aug 2014
Posts: 1,627
Likes: 175
From: North pole
'01 base M6 with a ton of miles. Been my daily for 4 years now. My new commute hits a little traffic now and my car got wicked hot.
Sitting at a stop a mile from my exit I noticed my temp gauge was at 255. Nowhere to go, I crawled the mile to the exit and just before I jumped, the temp drops to 220. About 210 the whole way home. Check fans, coolant, all looks good. Next morning 40 degrees doing 65 temp goes up to 250, then drops, up, then drops. Get to work, call NAPA, order thermostat and swap it out, complete flush and fill.
Now when I hit traffic it goes up to 235, but that's all. I used the OE 187 temp, I have a 160 on the shelf. 235 is hotter than usual but my commute is different now. Still hotter than I fell comfortable with. Runs cool flogging on the twisties in the woods all day.
So should I go with the 160? Or just plan on a water pump and radiator this summer?
Sitting at a stop a mile from my exit I noticed my temp gauge was at 255. Nowhere to go, I crawled the mile to the exit and just before I jumped, the temp drops to 220. About 210 the whole way home. Check fans, coolant, all looks good. Next morning 40 degrees doing 65 temp goes up to 250, then drops, up, then drops. Get to work, call NAPA, order thermostat and swap it out, complete flush and fill.
Now when I hit traffic it goes up to 235, but that's all. I used the OE 187 temp, I have a 160 on the shelf. 235 is hotter than usual but my commute is different now. Still hotter than I fell comfortable with. Runs cool flogging on the twisties in the woods all day.
So should I go with the 160? Or just plan on a water pump and radiator this summer?
Drifting
Joined: Mar 2013
Posts: 1,496
Likes: 353
From: Little Rock Arkansas
If it's been your daily for four years I'd imagine the radiator has a ton of junk in it. It probably needs to be properly cleaned (I actually went as far as removing mine from the car to clean it). Also if you haven't had coolant service performed it would probably be wise to have a really good flush performed and properly 'burped'.
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,883
Likes: 76
From: Portland OR
I should have mentioned I did check the radiator. Not bad, but could be cleaned. A new one from Rock Auto was about $100. My thoughts were if I was going to remove it, replace it with new and do the water pump while it's out. The thermostat took all of 20 minutes.
I used Red Devil radiator flush after 3 cycles of water followed by 3 more water cycles followed by 1.5 gallons of DecCool and 1 gallon of distilled water to the .5 hose water that didn't drain out.
Both fans seem to be kicking on. Maybe I will try to clean it, then replace if I jack it up.
I used Red Devil radiator flush after 3 cycles of water followed by 3 more water cycles followed by 1.5 gallons of DecCool and 1 gallon of distilled water to the .5 hose water that didn't drain out.
Both fans seem to be kicking on. Maybe I will try to clean it, then replace if I jack it up.
Last edited by 66dts-v; May 4, 2018 at 02:40 PM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Pro
Joined: Apr 2017
Posts: 590
Likes: 134
From: Hanover Maryland
He means the center lower air dam. Big piece of black plastic with a slant to it. Feeds air directly into the rad/condenser, its basically the nozzle for the hoover vacuum that is the C5. It's got springs and is most definitely scraped up from driving. Pretty important for air flow at speed, assuming it helps the fans out too. Look under the front of your car and make sure its there, especially after recent front end body work.
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,883
Likes: 76
From: Portland OR
Hmm, not sure I have something like that under the front, I will go look at lunch and see. Anybody got a pic of what is SHOULD look like?
Thanks for all the help on this.
<edit> found it, thanks to the repair video by Frogy, awesome.
Thanks for all the help on this.
<edit> found it, thanks to the repair video by Frogy, awesome.
Last edited by 66dts-v; May 4, 2018 at 03:21 PM.
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,883
Likes: 76
From: Portland OR
It's tough to see under there, but it looks to be in place, beat to hell, but there. I will watch Frogy's video when I get home and make sure it is functioning properly. Thanks again for the help with this.
1/4 mile/AutoX
Joined: Jun 2014
Posts: 11,441
Likes: 2,186
From: Buffalo Texas
I should have mentioned I did check the radiator. Not bad, but could be cleaned. A new one from Rock Auto was about $100. My thoughts were if I was going to remove it, replace it with new and do the water pump while it's out. The thermostat took all of 20 minutes.
I used Red Devil radiator flush after 3 cycles of water followed by 3 more water cycles followed by 1.5 gallons of DecCool and 1 gallon of distilled water to the .5 hose water that didn't drain out.
Both fans seem to be kicking on. Maybe I will try to clean it, then replace if I jack it up.
I used Red Devil radiator flush after 3 cycles of water followed by 3 more water cycles followed by 1.5 gallons of DecCool and 1 gallon of distilled water to the .5 hose water that didn't drain out.
Both fans seem to be kicking on. Maybe I will try to clean it, then replace if I jack it up.
Safety Car
Joined: May 2016
Posts: 4,667
Likes: 1,849
From: Erlanger, Kentucky
it's not the inside of the radiator to be cleaned but the outside fins !!!!!!
Also, if you are going to take the radiator out to clean it, you might as well just upgrade and get a DeWitts radiator.
You won't overheat with the DeWitts as long as everything else is working and the fins are clean.
Last edited by Spaceme1117; May 4, 2018 at 04:54 PM.
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,883
Likes: 76
From: Portland OR
The face of the radiator is clear of anything big like leaves, but there might be crap packed in it. I'll take a look at the DeWitt setup. But if the OE has worked this well for 17 years, I figured an OE replacement should outlast me. 
Safety Car
Joined: May 2016
Posts: 4,667
Likes: 1,849
From: Erlanger, Kentucky
I think the DeWitts is one of the best upgrades you can do to the Corvette, even if you are stock. It has twice the cooling capacity. The main benefit I find from it is that my coolant temps are very even and stable. With the stock radiator, if I was in traffic in the summer, temps could get up to 225 then they would drop back down once I got moving.
With the DeWitts, it doesn't matter if it is summer at 95F, in traffic, winter, etc. The temp stays at about 190 and doesn't move.
Even better if your car is an automatic as the DeWitts will definitely keep your trans fluid much cooler which is really good for an automatic.
Thread Starter
Drifting
Joined: Jan 2012
Posts: 1,883
Likes: 76
From: Portland OR
Damn, just not sure I am willing to spend $600-$1100 for a radiator setup. I think after I do a couple more things I will get a new OE pump and radiator.
I have put off things like new plugs and wires and my back tires have about a month left. Add it to the list. I just keep reminding the wife "it's cost us almost nothing in the time we've had it". But a clutch last year (LS7 with LS6 hydros), all new brakes, wheel bearings and ball joints are killing that argument. Now I have to say "but we won't have to touch it for another 17 years"
I have put off things like new plugs and wires and my back tires have about a month left. Add it to the list. I just keep reminding the wife "it's cost us almost nothing in the time we've had it". But a clutch last year (LS7 with LS6 hydros), all new brakes, wheel bearings and ball joints are killing that argument. Now I have to say "but we won't have to touch it for another 17 years"
Last edited by 66dts-v; May 4, 2018 at 05:31 PM.
Melting Slicks
Joined: Aug 2014
Posts: 2,470
Likes: 460
From: East Windsor NJ
'01 base M6 with a ton of miles. Been my daily for 4 years now. My new commute hits a little traffic now and my car got wicked hot.
Sitting at a stop a mile from my exit I noticed my temp gauge was at 255. Nowhere to go, I crawled the mile to the exit and just before I jumped, the temp drops to 220. About 210 the whole way home. Check fans, coolant, all looks good. Next morning 40 degrees doing 65 temp goes up to 250, then drops, up, then drops. Get to work, call NAPA, order thermostat and swap it out, complete flush and fill.
Now when I hit traffic it goes up to 235, but that's all. I used the OE 187 temp, I have a 160 on the shelf. 235 is hotter than usual but my commute is different now. Still hotter than I fell comfortable with. Runs cool flogging on the twisties in the woods all day.
So should I go with the 160? Or just plan on a water pump and radiator this summer?
Sitting at a stop a mile from my exit I noticed my temp gauge was at 255. Nowhere to go, I crawled the mile to the exit and just before I jumped, the temp drops to 220. About 210 the whole way home. Check fans, coolant, all looks good. Next morning 40 degrees doing 65 temp goes up to 250, then drops, up, then drops. Get to work, call NAPA, order thermostat and swap it out, complete flush and fill.
Now when I hit traffic it goes up to 235, but that's all. I used the OE 187 temp, I have a 160 on the shelf. 235 is hotter than usual but my commute is different now. Still hotter than I fell comfortable with. Runs cool flogging on the twisties in the woods all day.
So should I go with the 160? Or just plan on a water pump and radiator this summer?
Drifting
Joined: Nov 2016
Posts: 1,660
Likes: 365
From: SF Bay Area
If it is only heating up to 235 and not going higher, it is functioning as designed from the factory. Whether or not you are comfortable with that is up to you, I wouldn’t worry much about it. You can program the fans to come on at a lower temperature or turn on the A/C, which also has lower temp limits.
Administrator
Joined: Mar 2001
Posts: 368,340
Likes: 24,779
From: In a parallel universe. Currently own 2014 Stingray Coupe.
C7 of the Year - Modified Finalist 2021
MO Events Coordinator
St. Jude Co-Organizer
St. Jude Donor '03 thru '26
NCM Sinkhole Donor
CI 5, 8 & 11 Veteran
Moved to C5 Tech.