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Mike Holleman
04-01-2005, 02:46 PM
I was asked a question today that I didn't have an answer for. Will an auotmatic trans run cooler in stop and go traffic if you go to neutral when stopped. Is fluid going through the trans cooler in neutral?
Thanks
Mike Holleman

myclone
04-01-2005, 05:46 PM
I was asked a question today that I didn't have an answer for. Will an auotmatic trans run cooler in stop and go traffic if you go to neutral when stopped. Is fluid going through the trans cooler in neutral?
Thanks
Mike Holleman

Thats kind of an interesting question and could probably be argued about by us car guys for eons. From a GM trans standpoint and ONLY considering fluid temps at the cooler I would say that you would drop the temps slightly by going to neutral while sitting still.

On GM trans' the fluid goes through the cooler in any gear. Dunno about the ford and mopar stuff though.

On the other hand the constant apply/release of the forward clutches will prolly shorten their life some so IMO any benefit to putting the trans in neutral in stop and go traffic will be offset by clutch wear as well as beating the driveline to death over time due to driveline slop.

Mike Holleman
04-02-2005, 05:09 AM
I appreciate the responce. The question came up because I'm remounting my trans cooler to make way for an A/C condenser. The only times I have seen the trans temps high(above 180) is either in stop and go on a very hot day or when I drive long periods in third (it's a 700R4) since the converter does not lockup. We were trying to figure out if the cooler has fluid circulating through it when stopped.
64 Tempest Custom Conv. 421 Tri Power

gmachinz
04-02-2005, 12:51 PM
What kind of car are you working with? I designed a remote transmission cooler w/AN fittings and a 9" fan w/steel shroud which mounts in front of the radiator support and it accomodates even a Vintage Air AC system-it is designed to maintain a 150-155 degree temperature. I mocked this kit for a '69 but it can fit just about anything. Email me and I'll send you some pics just to give you an idea of the install. -Jabin

myclone
04-02-2005, 03:33 PM
(it's a 700R4) since the converter does not lockup.

Mike,

FYI, if the trans is set up to operate as a stocker then the TCC (torque converter clutch) should lock in 3rd. I dunno how your trans is built/set up but a 700 should lock in 2nd, 3rd, and 4th gears. If yours isnt locking then it may be something to look into since the trans fluid gets HOT with an unlocked coverter at speed.

FYI II, there should be fluid circulating through the cooler at all times on a 700 and the only thing that the fluid doesnt circulate through is the torque converter when the TCC is applied. Essentially the fluid is "trapped" in the coverter during lock up but everything else in the trans is bathed/supplied by fluid from the cooler.

HTH

Mike Holleman
04-02-2005, 05:07 PM
The 700R4 is a Bowtie Overdrives level 3 trannie. It is set up for OD lockup only. It is behind a built 421 Pontiac in a 64 Tempest conv. Ron Davis racing radiator with trans cooling plus a B&M cooler with 7 inch Spal fan. The trans generally runs at around 150 and only heats in hot weather and stop and go and then only runs up to maybe 180. If fluid is being pumped at idle the cooler should still be functioning. Thanks a bunch for the input.

gmachinz
04-02-2005, 07:07 PM
If you haven't already, try running a full synthetic tranny fluid. I don't know what the Spal 7" moves for air-mine moves right at 2100 cfm-and that's just for the tranny cooler. Maybe your main shroud is not at optimal performance for drawing out extra heat at idle. Does your engine temps go up at idle too? Maybe since the coolant temps are rising, it's making the tranny fluid rise as well. Just a thought. -Jabin

myclone
04-02-2005, 07:58 PM
The 700R4 is a Bowtie Overdrives level 3 trannie. It is set up for OD lockup only. It is behind a built 421 Pontiac in a 64 Tempest conv. Ron Davis racing radiator with trans cooling plus a B&M cooler with 7 inch Spal fan. The trans generally runs at around 150 and only heats in hot weather and stop and go and then only runs up to maybe 180. If fluid is being pumped at idle the cooler should still be functioning. Thanks a bunch for the input.

Ok, I understand now. With the above info you should be good to go. Keep an eye on those temps though if you beat the car at the track and if the temp heads north of 220-ish deg let the trans rest a while to cool some. The trans's life span will thank you later.

Mike Holleman
04-03-2005, 05:59 AM
Jabin, Your exactly right about the engine temp bringing the trans up with it. Pontiacs are notorious for running hot. That's why I went with the Ron Davis rad. It is fully shrouded with twin 12" fans and keeps the 421 well below two hundred even in traffic. But my trans needs to run much cooler and that is what caused me to add the B&M cooler. Bowtie says the trans temp should stay around 160. Before the B&M was added it would climb up to and above the engine temp. I am running synthetic fluid. Hopefully I will still have no trans cooling troubles by adding the A/C. Thanks to you and Myclone for the input.