ATF drains, flushes, and other fluid questions.

[daugherty83]

So, after having my tranny cooler oh so nicely mixing my coolant and atf fluid two years ago, I had a donor transmission installed with 36,000 miles on it. I was doing some camping last summer in the moutains in Northern AZ where I currently live and had an ATF temp light come on. I've now decided I want to go with a synthetic fluid and am at a crossroads. A lube shop will flush the tranny and pump in the fluid of my choosing that I bring to them for 69 bucks. Or I can have a reputable tranny shop in the area do the flush as well as drop the pan, roadtest, etc. etc., for a considerable amount more depending on what type of fluid I want. Or I can find a resident of the Phoenix Metro area to help me with a fluid flush using the motor and bucklet method described here in the past. Where are you AZ residents?? :hello:

My question is the tranny shop is pushing the T-IV fluid even after I told them I have an 01' and any Dex III or Synthetic will be fine. They are insisting that is what they need to use and I disagree. Also, if I do decided to just use the drain plug and fill method, can I mix say Mobil 1 or Castrol Syntec in with my regular Dex III that I assume is currently in the tranny? Also, if I use the lube shop how many quarts of fluid will I actually need? I assume it will be more than the standard tranny capacity do to flushing out the old. Are we talking around 15-16 quarts for a full flush? Thanks as always guys.

 

[thatgreentruck]

I would just drain and fill 4-5 times with a 3-5 mile drive between each. Shouldnt be a problem to mix. That's exactly what I did and it's not a problem. It's just like filling the crankcase w synthetic for the first time. They're meant to be compatible.

 

[daugherty83]

Oh ok, that def. sounds cheaper for the time being. May not be able to afford draining and filling repeatedly all five times to start but one or two should be fine for now. I am seeing 5 qt's of Syntec full synthetic with a Mobil 1 filter for 32.99. Seems like a great deal. Any suggestions?? Also, how many quarts can I expect to drain by removing just the drain plug?

 

[HCurphy]

I don't know if my advice is worth taking, but i'll give it anyway. I've switched to the castrol you mentioned, and i did it just like thatgreentruck mentioned above.

The difference, my "old" fluid was in decent shape. So, i didn't see the point in wasting it. I did a drain and fill with every other oil change for a while and still do it, but less frequently now. (probably took like a year to completely dilute out all the conventional) But, i mixed synthetic with conventional and didn't have any issues so i think you should be good to go.

I'll try to remember to come update this in the event my transmission falls out tomorrow because i was wrong.

Good luck.

 

[waketek516]

was JUST about to post the same question! Interested in answers as well...

 

[daugherty83]

I don't know if my advice is worth taking, but i'll give it anyway. I've switched to the castrol you mentioned, and i did it just like thatgreentruck mentioned above.

The difference, my "old" fluid was in decent shape. So, i didn't see the point in wasting it. I did a drain and fill with every other oil change for a while and still do it, but less frequently now. (probably took like a year to completely dilute out all the conventional) But, i mixed synthetic with conventional and didn't have any issues so i think you should be good to go.

I'll try to remember to come update this in the event my transmission falls out tomorrow because i was wrong.

Good luck.

This is very good to know bud, haha. Thanks as always. Haven't been on the forums in quite awhile but getting correct and unbiased information so quickly has always been one of my favorite parts about this place!

 

[CanadianTRD]

So, after having my tranny cooler oh so nicely mixing my coolant and atf fluid two years ago, I had a donor transmission installed with 36,000 miles on it. I was doing some camping last summer in the moutains in Northern AZ where I currently live and had an ATF temp light come on. I've now decided I want to go with a synthetic fluid and am at a crossroads. A lube shop will flush the tranny and pump in the fluid of my choosing that I bring to them for 69 bucks. Or I can have a reputable tranny shop in the area do the flush as well as drop the pan, roadtest, etc. etc., for a considerable amount more depending on what type of fluid I want. Or I can find a resident of the Phoenix Metro area to help me with a fluid flush using the motor and bucklet method described here in the past. Where are you AZ residents?? :hello:

My question is the tranny shop is pushing the T-IV fluid even after I told them I have an 01' and any Dex III or Synthetic will be fine. They are insisting that is what they need to use and I disagree. Also, if I do decided to just use the drain plug and fill method, can I mix say Mobil 1 or Castrol Syntec in with my regular Dex III that I assume is currently in the tranny? Also, if I use the lube shop how many quarts of fluid will I actually need? I assume it will be more than the standard tranny capacity do to flushing out the old. Are we talking around 15-16 quarts for a full flush? Thanks as always guys.

Avoid the flush. Never flush. Too many delicate parts and supple seals in a transmission.
If you feel comfortable, drop the pan, change the filter, clean out the valve bodies with Brake Cleaner or just...
Drain and Fill @ The radiator port all 13 Qts of ATF. (yours may take more)
Mixing Synthetic and Regular is fine, ATF is a very basic lubricant, not a lot of high tech involved. Frequent changes is better for your transmission than spending any amount of premium for fancy Synthetics. If you are living in a cold climate, Synthetic is more important.

 

[daugherty83]

It never ceases to amaze me though how these shops and their techs and mechanics refuse to listen to vehicle specific info that the customer may have. Whether its the DEX III issue or someone trying to fill your PS reservoir with PS fluid instead of DEX III ATF like it should be. I suppose they are not in the business of specializing in a specific make and model year range of vehicles like the 3rd gen. but it is always amazing how much more accurate and knowledgeable these boards are.

 

[CanadianTRD]

Also make sure your radiator is in excellent condition, particularly if you ever tow. Keeping your fluid temperature controlled is crucial, particularly in these big trucks. If you roast your fluid just a few times, it doesn't matter how new the fluid is or how expensive it was. It'll roast the same. Synthetic does have a higher molecular breakdown point, but when you are talking about temps in that range, in my mind you are already in trouble with either fluid.

I would highly recommend a:

 

[thatgreentruck]

I think is was about 4liters (1 jug) per drain.
I agree with the statements above. If it's greater than 30k I wouldn't do a power flush. A drain is good every couple years though.

 

[TegoXR]

So I can put AMSOIL synthetic tranny fluid after I drain the 2-3 quarts out of the tranny and there wouldn't be any issues of the oils mixing? And if I were to keep draining it and refilling with synthetic every two months let's say, eventually it would dilute the old oil out. Someone correct if I'm wrong.

 

[Nunyabiz]

The best thing to do is to take it to a T-Tech machine, full fill is about 11 or so quarts of Amsoil ATF but if you have an external cooler add at least a qt for that and also at least another qt on top of that to make sure you get 100% of the old out.
If you drive it hard, lots of off road and trailer towing I would also go with the Amsoil Torque Drive ATF. 3.5 gallons will cost about $165 for the ATF and you should have a little bit left over.

http://www.amsoil.com/storefront/atd.aspx

The T-Tech method uses the trucks own trans pump to slowly push the old oil out and the new in, no "flush" involved.

If you haven't dropped the pan it is always a good idea to do that because that is really the only way you can check anything, look at the magnets and how clean or dirty the bottom of the pan is.
Don't worry about a "filter" because we don't have one, it is just a fine stainless steel screen which unless something is wrong should be spotless and looking like brand new.

 

[jmildoc]

thanks, i think this will be my next thing to do on my 4Runner as far as maintenance. I dont know what fluid is in this thing at all so I am changing them all out as I go. I have had ill effects changing to synthetic in the oil (not tranny) in the past and always develop a leak so with this one I think I am going to stick with regular fluids and just change them often.

nunyabiz, wouldnt a "t-tech" machine do the same thing as you could do with filling the tranny while draining it from the line that goes up by the radiator? I think I will drop my pan, clean it, paint or degrease the outside depending how it looks and fill with some good ole DEX 3 and maybe 1 qt of the lucas tranny treatment.

 

[Nunyabiz]

thanks, i think this will be my next thing to do on my 4Runner as far as maintenance. I dont know what fluid is in this thing at all so I am changing them all out as I go. I have had ill effects changing to synthetic in the oil (not tranny) in the past and always develop a leak so with this one I think I am going to stick with regular fluids and just change them often.

nunyabiz, wouldnt a "t-tech" machine do the same thing as you could do with filling the tranny while draining it from the line that goes up by the radiator? I think I will drop my pan, clean it, paint or degrease the outside depending how it looks and fill with some good ole DEX 3 and maybe 1 qt of the lucas tranny treatment.

Yes it is basically the same as that method but you need 2 people to do that without making a huge mess and wearing yourself out getting in & out of the truck a few dozen times. But either is far better than draining and replacing just 3-4 quarts at a time, IMO that is just a waste of good ATF.
The synthetic ATF/Oil/Gear lube is better all around than petroleum but to each his own.

 

[Johnate0]

Did I read that right that it's not a good idea to do a flush on your tranny? Rather, just drain and refill several times within a week or so to effectively cycle all the old oil out? Does doing it this way get everything old out of the torque converter as well? My '01 had 165K on it and I've done nothing with the tranny fluid since I bought it at 83K. I was planning on getting a complete flush done soon but should I just drain and refill myself?

 

[Nunyabiz]

Did I read that right that it's not a good idea to do a flush on your tranny? Rather, just drain and refill several times within a week or so to effectively cycle all the old oil out? Does doing it this way get everything old out of the torque converter as well? My '01 had 165K on it and I've done nothing with the tranny fluid since I bought it at 83K. I was planning on getting a complete flush done soon but should I just drain and refill myself?

I wouldn't just drain & fill on a trans with that many miles without looking at the pan.

I would drop the pan and do a complete fill, either use a T-Tech machine or get a friend to help and do it through the radiator line and try to get as much as you can drained.
Would you do that with your engine oil?

 

[Johnate0]

Well yeah I would certainly drop the pan and check the magnet and such. I didn't know that after a certain amount of miles on the car that a true tranny flush is a bad idea though. Makes sense I guess