Transmission fluid level - should pan or frame be level

I plan to do a drain and fill for the transmission fluid this weekend. When setting the level, it's unclear to me how best to level the vehicle. I've seen people level off the bottom of the transmission pan, the frame, or just have the vehicle on level ground.

I sort of imagine it's not the biggest deal since I've seen it done all three ways, but was curious if anyone knew and could recommend a direction. Thanks!

 

I think if you precisely measure what drains out of it, and replace exactly that much, the levelness won't be an issue.

Just kind of thinking out loud here, but if you had it on a shop that used a chassis lift, the frame would be level to the ground. However, if they did it on an alignment style lift that you drive on, the vehicle itself would be level. Probably doesn't make a huge difference overall if you're putting in the same amount that you took out.

Incidentally, I also see a lot of how-to videos are very specific about the temperature. Again if you're replacing the amount that you drained, I don't see how that really matters too much.

 

I don’t disagree with your assessment, but it seems to me that measuring exactly what drained out may be difficult. When I change oils, a lot of the residue sticks to the drain pan.

 

When I watched the Vikings garage video on this, he drained the fluid into a clear container with markings on it, like what you might use in a lab or in baking.

 

I've always leveled mine to the frame and havent had issues.

I doubt to the pan is a major difference.

I still use a marked clear container as well to get a general idea of how much fluid I actually need.

 

Most Toyota owners never open the hood and rely on a shop for maintenance. A shop would put the vehicle on a lift, and the frame would be level.

 

Thanks for the replies! Yeah I was planning to use a marked container to get a sense of how much I drain and put back around 1/2 quart more than that. Then do the fluid level temp check and see how much drains out. I'd expect roughly 1/2 quart assuming it was filled correctly at factory. Just wanted to make sure how the vehicle was leveled doesn't change the final fluid level too much. I can't imagine it would be really sensitive to that difference. So I'll probably try to get it reasonably level at the frame and call it good.

 

I’ve used the pan to level and drained it in this from Amazon $14

 

My OCD tells me, ASSuming the previous person did the job right! For me, i just follow the instructions A to Z. My OCD/ professional habits from wrenching on helicopters for 30 years. Each is own.

 

dont forget to add a 1/2 qrt more from what drained out when you do the twmp and drain sequence.

 

Curious whether your OCD tells you to level at the pan or the frame or something else before setting the fluid level.

 

NOTICE: This transmission requires Toyota Genuine ATF WS. After servicing the transmission, you must follow the ATF adjustment procedure. Maintain the vehicle in a horizontal position while adjusting the fluid level.

For me this is easy, where do you drive your vehicle? on the road? A level surface is how the vehicle is used.

 

Well i sure hope its not vertical.

 

I just had all the jackstands at the same height and did the whole temperature and check bolt dance so frame level.

As long as fluid is similar temperatures, you’ll probably be fine too with the measure method which I’m planning to do on a Chrysler next week.

 

even easier, magnet level on pan and jack up front in center of skid plate to level it. Saves a lot of work.

 

When I did it, I cold drain with pan level, drain 3.5 refilled 4, plugged in my scanner and idled to 105 and open check. Fastened it back up once the stream “broke” and turned onto the pan” not a “drip drip drip” per se. **EDIT: check plug while engine is running. DO NOT turn off vehicle doing this drain and fill while setting level.

I did shift through all the gears while waiting for pan temp. It was 84 at idle startup, so took me about 30-45 mins total.

next time I’m going to use the most shallowest 24mm socket I have. First time doing it, my fill plug it almost rounded. Almost.

No issues after 1k. And I’ve done full WOT and hard braking. Just to make sure. I plan to do it again in 15-20k. South Florida heat makes it a little warm. My pan temp average is 175-180 and TC can get up to 200 in stop and go, while being somewhat hard on it. But once lockup occurs it’s in line with pan

 

The pan is not level so you don't want to use the pan. Actually, the pan slopes down towards the front of the car, while the drain plug is in the back. Not the best way to design it. After I drained the pan with the truck on the ground, I jacked up the front a bit and got an additional 10oz or so of fluid out. Then I lowered it back down to add new fluid and set the level.

 

to me the bottom of the pan looks flat and the pan rails where the bolts are look angled when mounted to the trans.

 

Well this is cut and paste from service manual, this is not a space ship!