Tranny Question

So guys I'm thinking about getting a sex change....... Just kidding.....

Anyhow, I have 142,xxx on my 06 and I've serviced everything that needs to be serviced except for one thing.... you guessed it: the tranny. I tend to shy from them because they scare me. I have been told by old timers to stay away from a tranny flush and just change fluid. But the guys at my local shop say flush it. What's the deal? I don't want to do anything that will cost me a new transmission in the end.

 

Marvelous idea. As long as it's a DIY project.

@gearcruncher should have some solid input on that for you. I'd give my opinion/experiences, but someone will shout that's just anecdotal. So lets see if we can get a pro to weigh in for you. (you might try a search on his username and see if anything is already out there as well)

 

Flush it, just draining and filling it doesnt nearly do the job and is a waste if time, drain and fill is like partially draining your engine and topping it off, ot doesntndo the job and your just mixing old fluid with some new fluid.

 

"There's no such thing as chicks with dicks Johnny, only guys with tits!"
-Ted

 

Do we need a transvestite sub-forum?

 

No they would take that as discrimination

 

You have done the drain/refill service?

If yes, then do a full flush. If not, most trany mechanics will advise not to do a flush because the detergent agents in the new fluid may dislodge too much crud. Just keep doing the drain/refill but do replace the filter.

 

Old guys =old cars and old tech
New guys=new cars and tech old guys don't understand.

A lot has changed with transmissions over the years. As I agree crud will come out but Id rather it out then in. Once you flush it you will notice a difference in your shifts and that they've become smoother.

 

Half the people will tell you to drain and refill; the other half will say go ahead and flush it.

So here's my opinion. Assuming 6 cyl. engine.

Source 8-12 qts of transmission fluid, pan gasket, drain plug gasket, overfill plug gasket, refill plug gasket. More on this below.

There are all kinds of opinions here about which fluid to use. I am not going to enter into that argument. Use whatever it is you think is best. Drain the pan. After draining pan with truck flat on the ground, elevate the front with a floor jack. There's close to a qt. of transmission fluid on the other side of the filter. Most of that fluid will drain with the front-end of the truck elevated as far as your floor jack will take it. Lower the truck after draining. Pull the pan and clean it and the magnets inside. Pull and wash out the screen-like filter. If you didn't elevate the truck to drain the fluid on the back side of the filter, you're going to be the recipient of the fluid that will fall when you pull the filter. Reinstall pan with magnets, filter and new pan gasket. The 6 cyl engine Tacoma has a pan gasket. You can look up that part number and the others mentioned above at www.partsouq.com; then source from your local dealer. Some people may get away w/o changing the gaskets. I always change them. The 2 gaskets on the bottom side of the pan are crush washers and tend to leak if reused.

In my experience, a properly filled A750x transmission will drain approx. 4 qts. - approx. 3 from the pan and approx. 1 with the front end elevated. Measure what you drain and refill with that same amount. Go thru the procedure documented in another thread to check fluid level. Drive the truck. How far? It doesn't take a lot of driving to mix the new fluid with the old.

Repeat the drain/fill process again. You may even want to do a 3rd drain and refill.

This process is known as a rotation drain. I've been doing them on vehicles that have no converter drain plug for many years This process has served me well. I've never lost a transmission, but I also do not believe in these extended drain intervals that car mfgs. recommend. Those are for people who trade in their cars every 5 yrs. My 2 cents.

Again, you need to do whatever method you think is best for you.

 

That's the idea of multiple drain/refills. If only flush it, the detergent agents will dislodge crud and it remains in the trany, potentially causing damage until the next flush. With 2-3 drain/refills, you drain/refill every 1K miles or so, removing crud a little at a time as the new ATF slowly mixes with the old ATF.

 

So I guess the general consensus here is do either one but it's best to do it multiple times?

 

With that many miles and you've never done any drain/refills, I say do the multiple refills to be safe. But, when to replace the filter? At the 1st drain/refill or at the end? Maybe both times?

Gearcruncher is the resident trany guru. Where he be?

 

I like the advice above. Read other threads about fluid choice. Valvoline maxlife synthetic carries the elusive "ws" rating that our truck requires. I did my sequoia. Drained pan, dropped it, magnet cleaned, filter and gasket. Got out 5 qts. Replaced all the stuff, poured in 5 new qts. Pulled off return line from the radiator wher it came back to the trans. Started up the truck, caught 4 qts, shut it off. Pour in 4 more, start it up and catch 4 more. Did it three times until the fluid comin back was clean. Put the return line back and poured in the missing four and added an extra 1/2 qt. fired it up and got the trans temp up to 130 via scan gauge. Took out the overflow and let it trickle out. (There are two plugs in the trans pan) make sure truck is jacked up level. I do this every 50k. Hopefully gear cruncher will show up and add to this.

 

No need for the sex change

 

I think
Lester Lugnut
had an excellent explanation of how to properly service a higher mileage transmission .
If you scroll back up to his post , it pretty much covers all the basics .
Its a higher mileage transmission that we are unaware if the fluid has ever been replaced , therefore the transmission pan and filter are both removed for a full cleaning and inspection .
This procedure eliminates the possibility of accidentally flushing contaminates from the transmission pan back into the valve body of the transmission .
Hydraulic spool valves inside your valve body ( shift valves ) are made of aluminum and your valve body is also made of aluminum . These spool valves stroke back and forth a " zillion " times during the life of a transmission .
If you keep your fluid clean and cooled properly , you lower the chances of these spool valves gumming up with fine particles of debris . The fine particles of debris floating around in your fluid works like sand paper and wears out the aluminum shift valves causing a loss of hydraulic pressure .
Considering that this post deals with the Aisn Seiki A750E , I will point you guys to a company that deals with valve body repair so you can see where the critical wear occurs in our transmission , what to look for and what can be done to your transmission without having to pay thousands for an overhaul if you catch it in time .
http://www.sonnax.com/parts/3477-zip-kit

I recommend this fluid servicing procedure for every transmission high mileage or not .
For those who simply say flush it , how do you know what kind of life the truck has had .
Was the truck driven hard ? Has it ever overheated ? Did the previous owner use it for racing etc etc .
There are thousands of variables that come into play when servicing a high mileage transmission .
Removing the transmission pan and filter is the best way to service any transmission

 

Mine was shifting roughly at 95k miles. Took it to the dealer in Panama City, Florida because my local dealer does not flush. Took them about 2 hours to give it back to me. When I drove away, I noticed an immediate improvement. Like a brand new transmission had been installed.

 

@gearcruncher.... By catching the old fluid from the return line, I am using the transmission to "push" out the majority of the old fluid by replacing it with new. I have assumed that it doesn't have the negative effects of the flushing machine. I do clean the magnets and change the filter. I use Toyota WS at 50k to prevent any warranty conflicts, but amsoil will be going in soon. Does an aftermarket cooler change the fluid checking procedure? Will I void my transmission warranty by adding it? I see some higher temps, 200-205 which made me decide to change fluid at 50k. The higher temps aren't sustained for more than a few minutes while going up grades when towing. Thanks agin for your knowledge, hope this isn't a hijack as it still pertains to transmissions.

 

I have always had jiffy lube flush the transmission at 30k increments. The process is pretty cool. They flushed it by disconnecting the fluid as it goes into the trans cooler the old fluid is pushed into the transfer pump as the new is flushed into the trans cooler and is circulated through the system. The problem with pulling the pan is that you won't get all of the fluid out of the system and you also will risk leaking fluid by removing the pan and resealing it. I'm sure I'll catch a bunch of crap from people but it was a relatively inexpensive way to maintain the transmission imo

 

This is really nonsensical. Flushing doesn't cause crud to magically wash over everything. It simply gets almost all of the old sheared transmission fluid out at one time. The pan drain and drive won't get half of the old fluid out if you do it 3 times.

12 quarts of old, remove 3 and replace. Now you have 9 quarts of old and 3 quarts of new that mix. Next drain will remove 3 more quarts, 1/4 of total capacity. 1/4 of those 9 quarts are old, 1/4 of the 3 quarts are new. So you remove 2.25 quarts of old and .75 quarts of new. You now have 6.75 quarts of old, 5.25 quarts of new. Not even halfway after 2 changes. Repeat. You will ALWAYS have a significant amount of the old oil left.

Flushing, as described in this forum, uses the transmission pump to remove fluid. No excessive pressure. No reverse flow. Just removing old fluid and keeping new. You end up with almost all new fluid, the only mixing happens in the torque converter. This business of flushing being bad is simply urban legend. Too many have done it successfully, myself included.

Changing fluids is NEVER bad, anywhere. Doing it too frequently is bad for your bank account, but not for your truck.

If enough people flush, it is statistically guaranteed that after someone flushes their transmission is going to die. It would have died whether they flushed or not. But those statistical anomalies still perpetuate this urban legend. This HAS to be why my tranny died, don't do it.

 

Why not do a flush to change all the fluid and then drop pan and replace the filter. Just have to replace the 5 quarts from the pan.