Thread: What Tranny Fluid should I run?

Well I actually meant that I was expecting it from you but I worded it all screwy so the punch has been lost, LOL.

I know what you meant, I caught it I just went to 3800performance.com and they sell the MSP cooler. It is $239.99 which is a chunk of change to throw down on a cooler, it looks like half of the cost is the lines and fittings. I dont understand why all of these coolers still route through the factory cooler. Sure it has its place, but you are buying an external cooler for a reason, it isnt to just marginally or try to help keep the fluid cooler, that IS the reason you bought it and with any high performance car that gets driven hard you need cooling that works well. Adding an external cooler will add capacity to the system, but my whole point is always why heat the fluid up to cool it back down? Running it through the radiator will certainly help heat the fluid up quicker but with fully electronic controlled transmissions and the advancements in fluid over the years i dont see the concern for this. When your stock cooler in the radiator gets a hole in it you are screwed and possibly trash your whole trans, or because of the design debris will collect inside and cause a restriction to further the damage to the new trans getting installed. Last weekend when we went up to the Detroit auto show we road up with a friend that just bought a new 08 GMC full size dually, 3500 I think, but it has the Duramax diesel and the Allison 5 speed auto. The dash lets you scroll through some engine data and trans temp. After 3 straight hours of driving the trans temp was all the way up to 115 deg F, yes that is NOT a typo! I couldnt believe it. They must use one killer trans cooler on those! But that just proves another point about the fluid not being warm enough causing problems, this is a factory vehicle and brand new at that with extremely low trans temps, they want it to last