[-X-]

Can someone explain how cold weather effects the trans fluid on startup drivability?

I'm especially curious how it effects the aftermarket fluids. I've noticed that both Dodson and WillAll offer a cold weather formula.

What do they consider "cold weather"? And what's the difference between the two?

 

[TodZilla]

-X- , Here are some of my thoughts.

The tranmission cooling is a heat exchanger immersed in coolant. During cold weather the heat exchanger should actually warm the trans fluid. After the coolant has reached normal operating temps the trans won't know the difference.

 

[-X-]

If you've ever watched your trans fluid, it doesn't warm up as quickly as the coolant. So during this period, the fluid seems to act differently.

Also, if the trans didn't know the difference, then why do companies have a normal and a cold weather formula?

 

[TodZilla]

The trans temp should come up slower than the coolant temp. As a matter of practice you should let a car like this warm up before hitting the road. Understood that sometimes its not feasible. There is definitely more to the equation than the fluid. As trans temps change the tolerances on moving internal parts change and they simply "act" different.

Vehicles with no means of controlling trans temp would probably experience more benefit from a cold weather formulation.

The question must then be asked. When the warm weather comes back should I change the trans fluid back to the OE spec? Is it feasible for most people to change trans fluid 2x per year?

Manufacturers of lubricants offer different products for different climates partially as a matter of marketing in an attempt to sell more product.

In most cases the manufacturer specs the lubricant and I've found that to be the best choice in most cases. In circumstances of extreme climates (Arctic) there would some benefit to the cold weather formulation.

Food for thought. I hope this helps.

 

[Martin Donnon]

We only recommend a cold weather transmission fluid formulation for sub 30F conditions.
Any properly specced transmission fluid should be able to operate across a wide variety of climates.
Do you have a specific issue here - X - ?
If so what combination of hardware and transmission fluid do you have?

 

[-X-]

My issue is this.

When the trans is cold the clutches do not engage properly. It slips when it should be upshifting. It happens in every gear, 1st and 2nd being the worst. Once the trans warms up, it drives like stock. Dodson seems to think it's the fluid and wants me to try a different blend "at my cost".

I wonder if there is something in the Cobb tuning that changes from cold to hot?

I have a Super Stock, stage 1 trans. We've pulled the trans apart and everything appears perfect.

 

[Martin Donnon]

We encountered this issue right back in the day (2008) when we were first experimenting with different blends of transmission fluid. Obviously the frictional properties of the fluid change dramatically with temperature, so providing there is nothing wrong with the transmission then getting the right fluid in the transmission will get the job done. We would normally recommend WR35BTDF fluid for this application