vroom_vroom

iTrader: (5)

So coming back from a road trip I started watching my trans temp as there are a lot of mountain passes with some serious grades.

How hot is too hot on a t56? It peaked at 231 but the normal operating temp is 180s

Anything I can do to get the temps down on it for future temps?

stevieturbo

Not something I've ever measured...obvious solution is install a pump/cooler.

Not necessarily the easiest solution though.

Or simply adding more fluid may well reduce overall temps. But it's rather unusual to have a trans temp gauge in the first place ? Have you been breaking boxes or something ?

imma_stocker

iTrader: (19)

Don't overfill the T56, it'll just leak out when it gets hot then you have a hot trans pushing hot ATF under the car. That trick only works with drag because its a short pass, not so good on incline and turns.

About 220 F the ATF will start to break down quicker but still fine in the manual trans. Not a real issue, just shortens maintenance intervals.

For an external cooler, it can be done with belt driven pump or electric scavenge pump through fill/drain ports without interfering with splash lubrication design. Not a lot of cfm required but the pressure needs to be able to push it through a cooler and back up into the fill port. Heat sinks on the pan or fans on the trans body won't make a big difference.

stevieturbo

Leak from where ?

I've always run 4.5 litres in mine since I've been using an LS, and that's some 13 years or so and never had any leaks.

No idea on temperature differences between gear oil and ATF, but I run a gear oil in mine.

I'd think with the turbos down low on mine and everything being pretty tightly squeezed in things could get hot, but I've never had any concerns or problems to actually monitoring temps

imma_stocker

iTrader: (19)

Wasn't aware the T56 could take gear oil without wearing faster.... good info. Gear oil can take more heat and abuse than ATF. Only downside IMO is the lack of detergents.

ATF is thinner and has detergents. ATF will expand more when heated while detergents clean leaks (opposite of stop leak lol) so puking from shifter or vent tube will happen easier than gear oil.


Ever figure what your issue was back in 07?
https://ls1tech.com/forums/manual-tr...ther-tube.html

stevieturbo

In the swap I had cut the breather pipe shorter than it should be, seemed like a good idea at the time. I extended it by 12" and it's been fine since. And it is noted that the problem only occurred after the trans swap...both boxes had been overfilled....and same box is still overfilled today. I was going to just stick the right amount in...but then figured what's the point, a little extra will always help, especially under hard accel and launches

People seem to use all sorts of oil in them, and all sorts of grades so hard to say what is right or wrong. OEM use ATF though, that is for sure.

imma_stocker

iTrader: (19)

Got curious and started looking up T56 stuff from the builders. RPM Trans recommends 4-5 qts of Royal Purple Synchromesh (synthetic gear oil with additives). That's very much inline with what you're doing... and what I'll be copying!

vroom_vroom

iTrader: (5)

one of the cooler dumb things the ctsv has is the trans temp gauge.

not sure why it "seems" to be running hotter than others have said but no circumstance is the same with multiple cars. the last trip i just got back from it peaked at 215f not much for grades but the cruise was set on 90 for a looooong time. its gonna build some heat with that secondary shaft spinning that fast for that long. i would still like to see it under 200 on the same conditions.

it gets changed out once a year so i suppose its not overly serious. tremec is not concerned until it hits 275f, then its dump fluid pronto. much more than that and im sure things will start to melt.

vroom_vroom

iTrader: (5)

car had the gauge oem. but i do have a notorious record of leading them out to pasture. pretty much exclusively with autos.