What is the correct temperature for checking ATF level?

[Samik8377]

Is the correct temperature to check ATF level via dipstick around 180F ? My manual says "drive for around 20 minutes to get the fluid to operating temperature and check with engine running, gear in P after moving through all gears" However this is subjective and dependent on ambient temperature.

 

[The Critic]

Depends on the vehicle - usually need to use a scan tool to verify fluid temp. But for most vehicles with a dipstick, operating temp is somewhere in the 170-200F range.

 

[MNgopher]

Ditto the Critic's comment - depends on the vehicle and transmission in question. My current units are 190+ to check hot. Previous units were 150ish...

 

[Rand]

Also some are hot and running some are not running.. and some have hot and cold marks on dipstick.
The difference between 140f and 170f is not the same as checking it when its 0f out in the winter cold.

 

[Trav]

180f is a pretty safe number if you don't have one from a FSM.

 

[Passport1]

What was the ambient temperature at the factory and the assembly line when fluid was first added to the trans in your car? Who drove it 20 minutes and checked it? Quantity or temp?

 

[The Critic]

What was the ambient temperature at the factory and the assembly line when fluid was first added to the trans in your car? Who drove it 20 minutes and checked it? Quantity or temp?

Factory fill is based on the unit’s published dry fill capacity.

 

[Soft Cars]

Fully hot with engine running.

 

[dnewton3]

Most OEMs will say something like "operating temperature", if you're lucky enough to have a dipstick.
Oddly, many Toyotas are something like 112-118F at the pan ... as if that's easy to decipher without a thermal gun and some estimation ...
My point is that each manufacturer will be specific either in the owner's manual, or service manual.

 

[Marcozi]

ZF (the manufacturer of many cars' transmissions) requires that the transmission be approximately 100*F when you check the fluid level.

 

[Hall]

However this is subjective and dependent on ambient temperature.

Not as much as you think. I doubt there's much difference in fluid temperature when it's 15ºF vs 95ºF if you're just driving casually, no excess loading, not pulling a trailer, etc. The vehicle's cooling system can handle the variation in ambient temperature.

 

[jetman]

97*f to 115*f for my no-dipstick Toyota A750e

 

[Brons2]

I tried to check mine on a cold day one time so I took off and drove for 20 minutes with my laptop runing Forscan plugged into the OBD port. The transmission never even got to triple digits. I gave up and tried again on a warmer day.

 

[twouvakind]

2016 Kia Soul, 140 degrees as measured by a scan tool.

 

[Jetronic]

Also some are hot and running some are not running.. and some have hot and cold marks on dipstick.
The difference between 140f and 170f is not the same as checking it when its 0f out in the winter cold.

The cold marking is often just a safe fill level to get the transmission up to temp and rechecked hot.

 

[The Critic]

The cold marking is often just a safe fill level to get the transmission up to temp and rechecked hot.

Technically true, though I've found that filling a trans to the cold min (when it is truly cold) puts the fluid level dead on.

 

[Rand]

The cold marking is often just a safe fill level to get the transmission up to temp and rechecked hot.

Which comes back to the major point that you need to list the vehicle to have a right answer there is no one answer fits all vehicles.

 

[Jetronic]

Technically true, though I've found that filling a trans to the cold min (when it is truly cold) puts the fluid level dead on.

truly cold, 40F? or 60F or 80F?

 

[The Critic]

truly cold, 40F? or 60F or 80F?

Room temp.

 

[UG_Passat]

VW-Aisin transmission is 95°F to 113°F