4 Cyl. Tranny Flush and Fill

I've seen the threads for flushing and filling the transmission on the 6 cylinder. But I haven't found a procedure for the 4 cylinder in the second gen Tacos. Can someone point me in the right direction? Thanks.
Also, if I go the easy way and just drain and fill, is it okay to refill with full synthetic instead of the T-IV that's in there? This will mix the two, as you won't get more than 3 or 4 quarts out from just a drain procedure. I would plan to perform more drain and fills over the course of 3 or 4 months in order to replace most of the T-IV. Would love to hear any thoughts/experience on this.

 

I want to know the same thing, is there any DIY to Flush/transfer out the tranny other than pan drains, and has anyone used a Full Synthetic tranny fluid other than using the Toyota T-IV in the tranny and what were any positive results in using a full syn fluid if any.

 

I'm sure the Flush process is similar to the 4.0V6 and easier since you have a dipstick and can fill the trans without crawling under the truck with a bottle pump. I've never done it on a 4 cyl truck but theoretically it should work. I have seen it done on a Honda Accord with the method below.

1.Drain the pan,
2.Replaced what was drained with new fluid.
3.force out a few quarts through the tranmission cooler lines
4.Repeat step 2 and 3 until fluid is clean and clear.

With this you're basically putting in new fluid and pushing out the old with minimal mixing. If you go the drain and fill route mixing the fluid should be okay as long as the new fluid type is compatible.
If your fluid is reallly dark and burnt I would definitely explore flushing the system, if its nice and red still you should be okay with a drain and fill.

 

To my knowledge, the only way to do a *complete* flush is to take it to a shop with a flush machine. I'm not familiar with the process of pulling one of the trans cooler lines and pumping out the old fluid that way, but since the fluid is pumped through the cooler I suppose it could work, just be sure to keep fresh fluid in the trans so it doesn't run dry (add thru dipstick tube). As Pabloeeto said, if your service is not ridiculously overdue (the fluid looks used but not ruined), a few drain/fills over a few months will change out most of the fluid. This is what many owners do. It's what I did at 60,000 with the T-IV fluid. Then at 120,000 I pulled the pan and replaced the screen and gasket -- everything looked great and I don't plan on pulling it again as long as I own the truck. That last time I used Castrol Import Multi-Vehicle ATF, which is highly rated for the Aisin automatics requiring T-IV. Drives great. Not sure about the synthetic ATF compatibility with T-IV but it really shouldn't be a problem, again assuming your trans is in good shape and not neglected. There are other threads on TW about flushing the 2.7 4-speed automatic trans.

Compatibility of Castrol Import Multi-Vehicle ATF: Meets Honda/Acura ATF Z-1; Toyota/Lexus Type T, T-III, T-IV; Nissan/Infiniti Matic-D, Matic-J; BMW LA2634, LT71141; Mitsubishi – Diamond SP-II, SP-III; Hyundai SP-II, SP-III; Volvo; ATF+3®, ATF+2® ATF+®; Ford MERCON®, MERCON® V; GM DEXRON®-III H and prior; Allison C-4

 

The T-IV is a great fluid. On a normally aspirated primarily street driven vehicle I see no reason to change it to synthetic. If some other type of overworking is going on, a cooler and a change to synthetic may be in order.

I have an '04 Highlander since new. A drain and fill every 30k has kept it quite happy for 111k and 14 years.

I've used Mobil 1 motor oil since the first change as well. A recent set of valve cover replacements revealed a nice clean top end.

My '13 5 lug uses the T-IV fluid, and I'll follow the same intervals.

It will also get Mobil 1 motor oil.

Interestingly enough, my '13 2.7 uses the same oil filter as the 3.3 in the Highlander.