DIY: Full Flush for Automatic Transmission

Neither do I.

 

woo..just read all 27 pages of this very informative thread. thanks mountain lion and everyone that's contributed their experiences here! i am looking forward to doing the flush sometime this week, but before I begin I have a few questions i'm hoping some of y'all could help me with:

1. I plan on doing the full pan drop and screen replacement. I'm at a little over 61k, but I bought the truck used with very little service history, and I don't know how rough the original owner was so I just want to get this done for my peace of mind. it was mentioned in somewhere in the thread that the pan bolts are prone to corrosion due to the design allowing for crap to get on the end of the threads. Is it ok to soak the bolts with PB blaster or liquid wrench beforehand? Would I have to be super careful and clean all the threads afterwards so none of it gets in the tranny? And someone mentioned torque ratings being "dry" vs. "wet" - how much of a concern is this?

2. I need to perform the output shaft seal replacement as it hasn't been done yet and there's clearly a slow leak of fluid on the output shaft. Should I do this before the flush, or after?

3. I don't have the tow package, and don't really plan on towing much, but I will be putting bed rails and throwing on a tepui, along with hauling a decent amount of camping gear for some long excursions, so I'm considering adding an aftermarket cooler. Should I install it inline with the radiator cooler, or bypass it? And again, should I install it before or after the flush?

Thanks for all the help!

 

I would fix the seal first then add the trans cooler if you like, but with only 61K i would not mess with removing the pan because the metal screen should be fine and doesn't need replacing, that's up to you....

 

Thanks for the input, that's probably the route Im going to go. I realize it's not necessary to change the screen but I really don't know how the original owner drove the truck and if there are any shavings I want to get them out for sure. It's probably overkill but at least I'll know the pan is clean!

 

Yep, do the seal replacement and add trans cooler first, preferably same day you do flush so that you don't have to top off ATF multiple times, which you will see can be a PIA, especially if adding ATF via the filler hole. I think torque on pan bolts is 50 in lbs, which seemed excessive to me - my other Toyota products call for 30-35 and that's what I went with and have no leaks (I check torque every other oil change).

RE #3, you can go either way with 'wiring' trany cooler with the radiator cooler. There are pros and cons to both. I prefer NOT 'cause you'll have more hoses that can break/leak on you. Mainly, 'cause if the radiator cracks (due to overheating, road debris, etc...) and leaks coolant into the ATF reservoir, you'll ruin your trany; ask the mid 2000 Nissan owners how that feels like! Just make sure the after market cooler capacity is equal or larger than current reservoir capacity (I don't know that that is).

 

Sub'd.

 

Thanks! Went with the

$59 hayden 679 universal 11” rapid-cool add-on transmission cooler to enhance cooling (not for direct replacement of the factory unit)

hayden 679, gonna do the bypass. only cons I seem to find to that is lower startup temp, but where I am at it rarely ever gets below 40F at night/dawn. I'd rather sit in the driveway warming up a lil longer than having to deal with radiator fluid in my tranny. Broken radiator is what killed my previous vehicle, which led me to getting the taco. Silver linings!

Any updates on this? Im experiencing similar symptoms, except in the mornings when I go to work and hit the highway. Though juxtaposing these two quotes one after the other makes me wonder if its a warm up issue..

Did you blast them from the bottom or the top, or both? And how meticulous were ya wiping of the excess pb before reassembling?

 

subbed for later

 

Thanks for the idea of the drill pump. Made changing the fluid so easy.

Used these tubes and the drill pump to pump the new fluid in. Didn't take very long!!!

Fluid had 61000 miles on it and wasn't too dirty.

 

50 in/lbs is only 4.17 ft/lbs.

 

When I started torqueing my bolts after having done so on my other three Toyota products, calling for 30-35 in/lbs and having same size bolts and pan gauge, 50 just seemed too high - it felt as if I was distorting the pan holes and the filter started squishing out. I stayed with 30 and don't regret, yet. I am constantly checking for leaks and re-torque them. Everything OK so far, and it's been about 30K since last ATF filter change.

 

Even 12 ft lbs for the strut tops on my Subaru's was easily exceeded with just 3 of my fingers on a 1/4" drive ratchet. I had to buy a special in lbs torque wrench when I modified my Cub cadet. Are you sure your torque wrench is in in lbs and not ft lbs?

 

Yes, I have three torque wrenches: quarter, three eighths, and half inch. Guess which is the in/lbs?

As I mentioned, torque for the other three Toyota products with same size bolts and pan thickness ranges 30-35 in/lbs. (Lexus ES350, Corolla, & Camry.) I will concede if I had done the Tacoma first, the other three may have felt under torqued.

 

Gotcha!

What size are the bolts? an M6 x 1.00 is supposed to be at 92 in/lbs dry; M5 x 0.80 at 54 in/lbs dry. Or the other possibility can be like the Brembo torque problem with STI's where they didn't convert it right and had everyone stripping their caliper mounting bolts tightening to 114.3 ft/lbs vs 114.3 N-m aka 80 ft/lbs.

 

Yep, M6 bolts. 92 inch is max, right? Whats the minimum? can be very low if you use threadlocker.

 

92 in lb is to meet the clamp load as 75% of proof load per ISO 898-1. Lubed, this number drops to only 69 in/lbs. (This is based on a 8.8 grade bolt.)

Edit: here's a cool calculator I found online: https://www.fastenal.com/en/83/torque-calculator

 

How many miles are you going between filter/strainer changes? Any pics? Most people say not to bother changing the filter, it's just a screen and shouldn't clog for a long time. What do you use to re-seal the pan, a preformed gasket or gasket maker?

 

i've done two ATF flushes: at around 70k and at 134K. Did filter change at 134k; used Beck Arnley

$37 044-0345 Auto Trans Filter Kit

044-0345. Next flush will be at 180K. Next filter change, at about 240K.

 

got my report back from blackstone, first tranny flush at 63k, nothing out of the ordinary

 

So your saying you can still go over 63k miles, not change the oil and it's still ok?