I'm about to change the transmission fluid on my car and like to doit while the engine is cold.When i did research they recomend to warm-up the car to operating temperature.
If i leave the fluid drain for 2 hours while cold shut be ok?

 

changing the fluid when cold is fine, it may just take longer to drain. 2 hrs should be fine. at worst you may leave a very thin film of fluid, but that won't be appreciated by the tranny.

 

take it on a 15 min drive warm it up and finish the job in 30 minutes.

 

Just out of curiousity, why do you prefer to do it cold?

 

i got my car on stands in garage due to cleaning engine and brake job.

 

Sounds like a good reason to me.

 

Yes but it gets much thinner when hot and will all drain. Warm it up and go for a 5 minute ride first.

 

I just did this last weekend. Intended to drain it while warm but was called away after putting the car on the jackstands. Drained in about 30 minutes and took almost exactly 2.7 liters to refill. Easy DIY.

I also did the front diff. fluid and cleaned the radiators while I had it up. Very satisfying day.