89RS_82Z

iTrader: (2)

700r4, cooler lines, on the rad, what one is the flow out of the trans and what one is flow back into the trans, need to know fixin to hook a cooler up, had trouble finding it on the net, the computer is acting real stupid and having trouble on alot of sites

Apeiron

The bottom line is from the trans to the cooler, the top is from the cooler to the trans.

punkdude908

don't mean to hijack the thread, but is there any way to easily fix or patch the tranny cooler lines? right now i have fuel injection hose as a patch- the lines were rubbing against the started and it eventually wore through. it's working for now, but won't last forever. i don't want to have to replace the entire line unless there's no other possible choice.

Air_Adam

You use power steering hose IIRC... thats whats used for the flexible section on a trans cooler hose.

AlkyIROC

Top line on the tranny goes to the top fitting on the rad. When using an aftermarket cooler, it doesn't matter which way the lines go. One will go out from the tranny to a cooler and the other returns, flow direction doesn't really matter.

As for new lines, you can use brake lines. Get the coil armored ones so they can easily be bent into shape.

89RS_82Z

iTrader: (2)

yea well getting mixed reviews on to use the stock cooler first, than the aftermarket.........others say just use the aftermarket one, and then it wouldnt matter what one to use

any thoughts on what route to go

AlkyIROC

If using an aftermarket cooler and with the stock cooler in the rad, you run the hot tranny oil through the external cooler first to bring the temperature down as much as possible. It then goes through the cooler in the rad. If still hotter than the engine coolant, the rad will bring it down some more. If too cold, the rad will bring it back up to operating temperature. Let the external cooler remove most of the heat then let the rad cooler maintain an operating temperature.

If you run the hot tranny oil through the rad cooler first, you're relying on the rad efficiency to bring the temperature down first but the rad is also trying to maintain coolant temperature. You're then running it through the external cooler which can bring the tranny oil temperature down too low.

Tranny oil, like engine oil, operates best in a specific temperature range. Too cold can be just as bad as too hot.

89RS_82Z

iTrader: (2)

what if my car is running 220, wouldnt that heat the trany up to much???

i am ditching the single row factory rad for a 2 row.....car only runs 220 with the a/c on.....other wise it runs 160-170

i would like to get a trans temp gauge, but im spending enough right now for the trans, cooler, trans pan, 2 row rad, reinforceing my control arms, panhard and tq arm


BTW for info to help on this, running a 700r4 Zpack racing clutchs, racing band, vette servo, 2200-2400 stall, and a custom shift kit, with a few more mods, pretty much a drag strip/racing 700.... Derale cooling trans pan, and a full sized truck/small motorhome trans cooler

only reason im worried about it is because my last trans was ruined due to heat, and it was BUILT also, only lasted 8k, but only running factory cooler


oh yea, not to say you are wrong, but i haven't heard of going through the rad last, always been told, and on other apps hook the rad up first..... dont you want your trans temp from 170-220??? that being said, aslong as your car is under 220 your ok..please dont take that as an insult Stephen 87, its not ment to be one, i just thought if you could get you trans at 170 that was its best

AlkyIROC

If your car is running at 220, tranny oil temperature is the least of your concerns. Normal operating temperature of the coolant, engine oil and tranny oil is around 180. EFI vehicles normally run at 195 just to reduce the emissions and many EFI vehicles, especially trucks, come from the factory with an external tranny oil cooler because the rad is now too hot.

When the engine is cold, so are all the oils. As the engine reaches operating temperature, so do the oils. If you're working the transmission or have a higher stall converter, the tranny oil temperature rises. It's not uncommon to see tranny oil at 240 which is reaching the "much too hot" stage.

That 240 oil should go through an external cooler. If the external cooler is large and efficient, it could bring the temperature down to 160. It would then go through the rad cooler to be brought back up to 180. That oil then gets used in the tranny then returns to the pan as hot oil to start the cycle all over.

If the cooler isn't efficient enough, the 240 oil may only come down to 200. The rad cooler will then bring it down to 180 before returning it to the tranny providing the rad is efficient enough to bring it down at all. If the rad is running too hot, all the oils will be too hot.

Now if the rad cooler was before the external cooler, 240 oil would need to be cooled by the rad cooler first. If the rad isn't efficient enough because it's also at it's limits to keep the engine cool, the oil may only come down to 220 because the fan is already working at maximum to remove the excess heat from the rad. It then goes through the external cooler which can either cool it down too much or not enough. The oil returning to the tranny for use by the hydraulic system is never being returned as a uniform temperature. If the rad is over efficient, the 240 oil is cooled down to 180 then goes through the external cooler which brings it down even more and now the tranny oil is below it's normal operating temperature.

The rad is the thermostat to the engine and tranny oil temperature. If the rad can't maintain a proper operating temperature, the oil temperatures will fluctuate.

As a drag racer, my tranny oil never stays at a uniform temperature. I try to get it up to operating temperature before racing but sitting between rounds, it cools right down again. Using a transbrake and a very high stall converter, it can build heat very quickly so a big cooler is used. The short time it's used under load isn't long enough to worry about having the oil too hot until later in the rounds when there isn't enough time for cool down. That's when I'll have the fan on when the engine is running to pull as much heat off the cooler as possible. There's little chance of me having tranny oil too cold so my goal is just to keep it from getting too hot. By the time the tranny oil hits 260, it starts to form varnish as it's getting cooked. If it hits 280-300, it's cooked.

I have a coolant temperature gauge in my car but running alcohol, it rarely gets above 180. I have an engine oil temperature gauge to let me know when the oil and engine are finally receiving some heat. I finally have a sensor in the oil pan of the transmission to see how hot the tranny is getting. The oil in the pan is how hot the oil is getting that's being used before it's sent to the cooler. As long as I don't cook the oil, I let the temperature swing as much as it wants in either direction.

Running alcohol, I don't need much of a rad. I use a rad from a Pontiac Firefly and my tranny cooler is about 3/4 the size sitting in front of it.

89RS_82Z

iTrader: (2)

yea i need a new rad, i know that, i hate to see 220 with the air on, i fact when it does that i normaly turn the air off and then it will get to the 160-180 range

i been tring to find one of the 2 row copper tank rads, but thats impossible

89RS_82Z

iTrader: (2)

just dropped $$$$ on an all alum racing rad.......now i hope the motor will stay cool even with the A/C on