Trans drain and fill question

Couldn’t find anything doing a search. I have a low mileage 2017 tundra and want to do a trans drain and fill because I’m hitting the 6 year mark. Should I just do a four quart drain and fill or should I do a complete fluid exchange? Is it common to mix old fluid with new with a drain and fill?

 

I’m in the same situation as you are. 2014 with 36k miles, and I tow a lot. I’ll be doing a drain and fill with Toyota ATF WS. Whatever amount is drained I will refill with new fluid, around 4.5qt plus a little extra. Then I’ll open the overflow plug and wait for tranny temps to hit 115 degrees, then close it up. I plan on doing this every 30k miles. You can do a fluid exchange to swap all the 13qts as well. Whatever you do, don’t do a power flush. It will loosen the built up deposits inside the transmission.

 

Just do the fluid exchange, it's not that difficult. If you have a couple of free hours you can knock it out. I've done it twice on my tundra following this guy's video.

https://m.youtube.com/watch?v=cB8MdGgwg68

You'll need almost 14-15 quarts of the toyota WS if you have the 5.7. You might consider valvoline max life if you want to go the cheaper route....which is what I've done twice with no issues at all.

 

Thanks for the reply. I don’t like the idea of mixing old fluid with new fluid but I guess this is considered a normal procedure? My truck use is pretty light duty. I only tow a few times a year.

 

At your year and mileage I'd do the drain and fill. Just make sure you check your level as mentioned above via engine temp.

 

If I was you I would do the front and rear diffs and transfer case if you have 4wd

 

Great video. Thanks for the info.

 

I’m going to do that next. Thank you.

 

Do you need more for a 4x4?

 

Same whether a 2wd or 4wd

 

Hey guys I have 2018 tundra 4x4 and I never towed anything. And I barely used 4wd. I am due for 65k oil change and I never did trans oil change. And my dealer is recommending to do it now. And also coolant change. But in owner manual it’s not suggesting to do any of these oil changes around these mileage. Should I do it now or wait?

 

I would do the transmission by 70 thousand, I don't think the coolant is supposed to be done u til 100 thousand but can't remember for sure.

 

Three words for you guys: drain-and-fill.

It's perfectly OK to mix new fluid with older fluid that's still inside the transmission. It's actually beneficial, as some of the additives in the new fluid will disperse throughout, helping the old fluid.

You should drive at least a few miles between, if you're going to do multiple spill-and fills.

I would do one now (which exchanges about 4 to 4-1/2 quarts give-or-take). Then you can drive the truck for a while, making sure the transmission doesn't misbehave.

If an older transmission get killed by a full fluid exchange, I think it's because the extreme cleaning-action of 100% new fluid loosens too much gunk, and it plugs passages and locks up solenoids. She's toast.

Individual spill-and-fill's over time can help avoid this doomsday scenario!

There's the belief that older fluid contains "grit", and that helps the clutches bite solidly. And if you exchange all the fluid, the new won't have this grit and the clutches won't engage as solid.

I'm not sure about that? Old fluid shouldn't contain grit, as the fluid passes through a filter in it's circulation cycle. The grit or impurities could be microscopic, but I'm not sold that can make a difference in clutch and torque converter function.

Old fluid is thinner, sheers easier at a given temp, and contains less helpful additives.

ON EDIT: To save $$, I've used Valvoline MaxLife Full Synthetic ATF in older Hondas, Subarus, Nissans, and Toyotas. Always mixing with what's in-there by spill-and-filling, and always have had excellent results.

No affiliation, just a satisfied long-term user...

ToolCat