. Especially if you have a high stall converter. I have a cooler on my auto '78 Z28.
Tranny or Engine oil cooler?
Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
Transmission cooler is more important. Essentially only cars that race and tow heavy loads require the use of an oil cooler, but automatic transmissions require one all the time.
Some older cars with automatics didn't come with transmissions coolers but engines didn't run so hot then as now plus transmissions weren't as sophisticated then as well. I have an SUV with factory tow package and it came with an oil cooler, but that was intended for more than just street driving.
Adding an engine oil cooler isn't a bad thing to do...just not required for street driving. Regular oil changes are more important. If you want to add an oil cooler go for it.
Some older cars with automatics didn't come with transmissions coolers but engines didn't run so hot then as now plus transmissions weren't as sophisticated then as well. I have an SUV with factory tow package and it came with an oil cooler, but that was intended for more than just street driving.
Adding an engine oil cooler isn't a bad thing to do...just not required for street driving. Regular oil changes are more important. If you want to add an oil cooler go for it.
Last edited by Roughrider; Aug 6, 2010 at 10:37 AM.
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
The only time you need an auxiliary engine oil cooler is if you're typically seeing oil temps nearing ~240*F or above. FWIW, thermostatic control valves are available.
Thread Starter
Melting Slicks
Joined: Mar 2004
Posts: 3,472
Likes: 18
From: Lake Ozark, MO
Makes sense. I had both mounted but never hooked up when I was turning the car into a Friday night only thing. Now that the wife wants to drive it more I'm taking most the stuff off that isn't really need or performance related.
Safety Car
Joined: Aug 2000
Posts: 3,711
Likes: 43
From: San Antonio TX
Indeed. You can not run an auto trans too cool -not talking harsh arctic temps here- and the cooler you can run it, the longer it will last. Engine oil needs to reach at least 212 degrees just to boil out the water from condensation. Unless the engine sees sustained high rpm (like running a steep gear for a long highway trip), it's not likely the engine oil will get close to the danger zone of 260 and up.
Le Mans Master
Joined: Oct 2007
Posts: 7,455
Likes: 977
From: RI, Now Franklin/Nashville TN
Indeed. You can not run an auto trans too cool -not talking harsh arctic temps here- and the cooler you can run it, the longer it will last. Engine oil needs to reach at least 212 degrees just to boil out the water from condensation. Unless the engine sees sustained high rpm (like running a steep gear for a long highway trip), it's not likely the engine oil will get close to the danger zone of 260 and up.
You definitely cannot run a tranny too cool under most conditions as noted above. I have been running tranny coolers external to the radiator (I do not run the lines into the radiator with tranny coolers-the tranny coolers do all the cooling) since 1978 rear round in various other cars I have owned. 1973 Nova SS auto with (2) tube and fin coolers-168,000 miles when sold. Currently, 2001 Pontiac Grand Prix with the crap 4T65E FWD transmission-(2) 18,000 GVW double stack Long coolers-101,000 miles on the tranny and a 1994 Mustang GT auto with one 28,000 GVW double stack Long cooler. Never had a tranny failure yet.
As for the oil, agreed that an oil cooler is not necessary on the street. However, this idea that the oil has to get to 212 degrees to burn off water vapor, I have not witnessed in 31 years of owning cars. Again, Nova SS had on oil temp gauge that I installed and the oil typically ran about 175 degrees. The 78 corvette has an 81/82 oil temp gauge where the analog clock used to be (I installed that back in the 80's) typically runs also 175-180 degrees and my 2010 Z06 oil temp gauge typically runs 175-180 degrees and has NOT gone over 200 degrees yet! Just an FYI.
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
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I had a chart from GM at one time that listed various temps and trans life expectancy based on those temps. I'm still looking for it. I know it's somewhere.
