What happens when an auto trans is cold?
The heaviest stress on an auto trans is when the trans is cold and it up-shifts quickly higher gears requiring heavy drive-train load. If you have a bad engine temp sensor, or a thermostat that is stuck open cold, it will provide a simulated cold operation value to the ECU and Trans telling it to continue to delay shift points.
Why does my transmission slip when it’s cold?
If your transmission slips only when it’s cold, then there could be three possible reasons. The first one could be that your engine is low on transmission fluid and could use some more. The reason it works fine once it’s warmed up, is because the oil expands with heat.
What to do when your transmission is cold?
Commonly, shift points and are delayed as well as overdrive disabled until the trans reaches full operating temperature. This allows the engine to heat up quicker, transmission to circulate fluid and heat up quicker with minimal stress on the transmission.
What causes a car to have a cold shift problem?
If you have a bad engine temp sensor, or a thermostat that is stuck open cold, it will provide a simulated cold operation value to the ECU and Trans telling it to continue to delay shift points. There are still many other reasons for cold shift issues, but the above are common reasons for cold failures.
What causes a car to have transmission problems in cold weather?
Transmission Problems in Cold Weather. A car having transmission problems in cold weather is a very common issue. The main reason behind it is, that the low temperatures increase the viscosity of the transmission fluid and it doesn’t flow smoothly in the system.
What happens to a transmission when it freezes?
When it freezes, it expands, and that can cause damage to the case and valve body in the transmission by creating cracks. If those cracks appear, the transmission cannot be rebuilt. This issue tends to be a major problem on certain Nissan vehicles holding an RE5 transmission.
Why does my transmission slip when the engine gets hot?
It isn’t when the engine gets hot, it is when the transmission fluid gets hot that the slipping starts, due to wear of the clutches and gears inside the transmission. First, check the fluid level to make sure it is full. If it is low, bring fluid level to full and see if that helps.
What kind of transmission fluid should I use in cold weather?
Use synthetic transmission fluid: Synthetic fluids behave much better and retain their given specs under cold weather conditions. Be sure to find the synthetic fluid designed for your vehicle.
The heaviest stress on an auto trans is when the trans is cold and it up-shifts quickly higher gears requiring heavy drive-train load. If you have a bad engine temp sensor, or a thermostat that is stuck open cold, it will provide a simulated cold operation value to the ECU and Trans telling it to continue to delay shift points.
What causes a transmission to slow down during cold shift?
Another area of cold shift issues, typically delayed shift issues, is the cooling system and related sensors. Most newer transmissions rely on a engine temperature sensor input to determine the proper shift points of the trans during cold operations.
Commonly, shift points and are delayed as well as overdrive disabled until the trans reaches full operating temperature. This allows the engine to heat up quicker, transmission to circulate fluid and heat up quicker with minimal stress on the transmission.
What can cause a trans to not drain back?
If the fluid level is high, meaning well above the cold full mark (a little high is typical), then you have a drain-back issue with the trans. However, you can still have an improperly torqued valve body that may not exhibit drain-back and still allow binding shift valves.