Automatic Transmission Fluids (ATF) full 12qt flush & set level, 100 series.
- Thread starter 2001LC
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I recently did 12qt flush for the second time, this time on my second 06 LX. You are correct, if you drain the pan you'll get around 2qt out. If you remove the pan you'll get another 1-1.5qt out of the pan. So you're probably ok since you're not counting the 1- 1.5 qts that remained in the pan. In my rig after all was done and counted, we removed 11qt and filled 12.3qt (exactly what manual states). My fluid was pretty dark, probably never changed before. If it was, then it was a long time ago and probably undefiled. I overfilled by one quart (13th) and used Tecstream for temp reading, got it up to 106 and drained 2/3 of a qt. The way I counted old fluid is I used one unopened ATF bottle by marking its factory filled level with sharpie, I later used that empty bottle to measure everything that came out of the tranny.
- Thread starter
- #63
To say one got out 10qt and add 12. For sure you'll get 2 qt out on level check, if A/T was at correct level before you began. One could get out 100 qts and add 102 qts. They get same results (2qts over), if AT level was correct in the first place.
I'll focus on 04-07 no dipstick. Although no real any difference in 98-03. Other than we can easily check A/T level pre flush, via dipstick.
First I'll say: I've flushed more A750f (03-07) A/T then I can remember.
In the 04-07 (no/dipstick). I don't often check level before draining the pan. Why; BK1 CAT, gets to hot for me to R&R fill plug. Yet I can say I'll find them ~1/3 qt low 95 out of 100 times. How do I known they're low, without checking level first. By very accurately measuring how much comes out, and how much I put in at same time as it comes out. Understand here. We don't drain and pump out all fluid until A/T dry. Then add. We add qt. by qt., as we remove. So A/T is never run dry. We're at most, ~1/2 qt low at any point engine running during our flush.
I get 3qt. from pan, every time. Even if A/T a bit low, I'll get 3 qt. on level ground. Even if AHC, in H. I get the same results.
How do I known, what level was, if not check pre-flush. By how much comes out during level check.
I can flush out 10qt., 12qt., 18qt., or even 100qt. The trick knowing exactly what has come out and exactly what I've put in.
The 04-07, was under filled at factory, by ~1/3qt. When I flush, I stop flushing, once 12 qts. out and 12.5 qts in. I work to stay 1/2 qt. over filled, during the flush.
Recap of a flush:
As I load (foot on brake, increase RPMs to ~1,200 while in a forward gear (D-1)) A/T, shift through gears slowly holding in each. Where I can see, A/T #1 & A/T #2. A/T #2 always goes up faster and higher, then A/T #1. As ATF #1, start to near 95F, I'll shift to P and idle. #1 continues to climb a bit and A/T #2 starts to drop. This is AT fluid temp equalizing, throughout the system. Note: If A/T #1 falls back, I'll load A/T again. Once I feel A/T fluid nearly equalized. I'll crawl under vehicle with tech stream. As I watch as A/T #1 raising and A/T #2 dropping. I shoot for #1 at ATF 97F and #2 ATF at ~106F<. I remove check plug.
At this point a get a steady flow from check plug, not just a drip. I'll catch maybe 1/8 qt to 1/4 qt. from check plug. Yet, I'd over filled by 1/2 qt. or more. This tells me, the A/T was low, ~1/3 qt.
More than ~1/3 qt out, of check plug at ATF #1 97F. I know it was over filled, by whatever extra beyond ~1/3 plus qt.
No flow, I'll take A/T #1 temp higher. To see if I get flow before hitting 115F. These are A/T that were lower, than the factory under fill.
When low, without dipstick. I'll add through cooler return line. Same hose, I pulled off nipple, on PS near top of rad. I use a very large syringe, to force in AFT in return hose.
I like to set level as high as reasonable. So I shoot for lowest ATF #1 temp of 97f. Even a bit lower temp is oaky. 1/3qt over is fine. Some AT shop like 1 qt over.
Did this 07LX yesterday.
I'll focus on 04-07 no dipstick. Although no real any difference in 98-03. Other than we can easily check A/T level pre flush, via dipstick.
First I'll say: I've flushed more A750f (03-07) A/T then I can remember.
In the 04-07 (no/dipstick). I don't often check level before draining the pan. Why; BK1 CAT, gets to hot for me to R&R fill plug. Yet I can say I'll find them ~1/3 qt low 95 out of 100 times. How do I known they're low, without checking level first. By very accurately measuring how much comes out, and how much I put in at same time as it comes out. Understand here. We don't drain and pump out all fluid until A/T dry. Then add. We add qt. by qt., as we remove. So A/T is never run dry. We're at most, ~1/2 qt low at any point engine running during our flush.
I get 3qt. from pan, every time. Even if A/T a bit low, I'll get 3 qt. on level ground. Even if AHC, in H. I get the same results.
How do I known, what level was, if not check pre-flush. By how much comes out during level check.
I can flush out 10qt., 12qt., 18qt., or even 100qt. The trick knowing exactly what has come out and exactly what I've put in.
The 04-07, was under filled at factory, by ~1/3qt. When I flush, I stop flushing, once 12 qts. out and 12.5 qts in. I work to stay 1/2 qt. over filled, during the flush.
Recap of a flush:
- Engine off and cool, drain A/T pan. Getting 3qts while on level ground. Replace drain plug with new washer, torque to 15ft-lbf.
- Remove fill plug and attach fill hose (04-07).
- Add 3 1/2 qt. to pan, through fill hose.
- Remove A/T cooler hose (PS near top of rad) from metal nipple coming from A/T oil cooler radiator (smallest of the three radiators, in front of other two).
- Attach catch hose to out flow nipple coming from oil cooler rad, and run to catch can.
- Start engine and idle.
- Add ATF in through fill hose, as ATF pumps into catch can. 2qts pump out, as I add 1 qt in fill hose. Stop engine, stopping ATF from pumping out. Add 1 qt. more, while engine off.
- (At this point I've 5 qts. out 5 1/2 qts in)
- Start engine 2 qts out as I pour in 1. Stop engine add 1 qt.
- (At this point I've 7 qts out 7 1/2 qts in)
- Start engine 2 qts out as I pour in 1. Stop engine add 1 qt. Note: by now ATF is looking much better.
- (At this point I've 9 qt out 9 1/2 qt in)
- Start engine 2 qts out as I pour in 1. Stop engine add 1 qt.
- (At this point I've 11 qts out 11 1/2 qts in). Note: by now ATF is looking very clear, like new.
- Start engine 1 qt out as I pour in 1/2. Stop engine add 1/2 qt.
- (At this point I've 12 qts out 12 1/2 qts in)
- Reattach return hose to nipple coming from oil cooler rad. Place hose on nipple at same depth it came off. Place clamp, on hose. in exact same impressing on hose. Use a flash light.
- Remove fill hose and replace fill plug.
As I load (foot on brake, increase RPMs to ~1,200 while in a forward gear (D-1)) A/T, shift through gears slowly holding in each. Where I can see, A/T #1 & A/T #2. A/T #2 always goes up faster and higher, then A/T #1. As ATF #1, start to near 95F, I'll shift to P and idle. #1 continues to climb a bit and A/T #2 starts to drop. This is AT fluid temp equalizing, throughout the system. Note: If A/T #1 falls back, I'll load A/T again. Once I feel A/T fluid nearly equalized. I'll crawl under vehicle with tech stream. As I watch as A/T #1 raising and A/T #2 dropping. I shoot for #1 at ATF 97F and #2 ATF at ~106F<. I remove check plug.
At this point a get a steady flow from check plug, not just a drip. I'll catch maybe 1/8 qt to 1/4 qt. from check plug. Yet, I'd over filled by 1/2 qt. or more. This tells me, the A/T was low, ~1/3 qt.
More than ~1/3 qt out, of check plug at ATF #1 97F. I know it was over filled, by whatever extra beyond ~1/3 plus qt.
No flow, I'll take A/T #1 temp higher. To see if I get flow before hitting 115F. These are A/T that were lower, than the factory under fill.
When low, without dipstick. I'll add through cooler return line. Same hose, I pulled off nipple, on PS near top of rad. I use a very large syringe, to force in AFT in return hose.
I like to set level as high as reasonable. So I shoot for lowest ATF #1 temp of 97f. Even a bit lower temp is oaky. 1/3qt over is fine. Some AT shop like 1 qt over.
Did this 07LX yesterday.
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re your first point: agreed 100%; however, why would i only get 2 qts out of the pan if it was on level ground? it seems like that is the real issue here.
also, on my version of TS, i only see one AT temp - can i just use this reading or do i really need #1 and #2 to converge? (which would require me getting a different reader)
also, on my version of TS, i only see one AT temp - can i just use this reading or do i really need #1 and #2 to converge? (which would require me getting a different reader)
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i think i would be more at ease if i was able to get 1+ qts more in than out, but it seems i was only able to put in [keep in] exactly what i took out, which just seems odd for a truck with 250k+ miles.
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Only 2 quarts drained out- How long did you allow to drain ? If you leave overnight you get additional fluid draining out-
interesting. i only let it drain for a min or two until the initial stream stopped. i guess my main question is what should i do now? am i good to go or should i do one more drain and fill on a garage floor (instead of my mostly flat driveway)? if i do another d&f, i will let the pan drain for a few hours.
it just occurred to me that i didn't remove the check plug during the drain process - maybe i should have done that to get more out of the pan? i doubt i would get that 3rd qt that i'm looking for, but maybe it would get me closer to 3.
- Thread starter
- #71
If on level ground, with ~3/4 rake. Engine & A/T, had been off and at rest for a bit. To allow fluid to settle. Or even sat over night. Then I'd assume you were low.
The 98-05, don't give us as many data points in tech stream. Same A/T A750f in all 03-07. Which both have AT1# AT#2 sensors. But the 06-07, gives us more data (PID), through tech stream. 2008- up a ton more PID, blow your mind more.
We set to ATF #1 temp. I talk about both #1 & #2. For 06-07. To illustrate, how temp varies in the system.
98-05 we only see ATF temp #1
- Thread starter
- #72
No need.
I usually let drain from just drain plug, while I get fill plug out and fill line in, set up catch can, line up 12 qt on my beach, get paper and pen, etc. Maybe 15 minutes. 3qts' even time, from cold A/T that was set near correct level.
If any doubt as to level now. Bring temp up and Recheck:
04-07 at ATF #1 97f to 115f. Add if needed.
98-03 at ATF #1 158f to 176f.
98-03, I under fill until level check. Where I can easily add into dipstick
04-07 I always over fill, until level check. So I don't have to add (in most cases)
My routine is to remove and clean oil pan and filter. You probably should've done that too, it only takes an additional 20-30min tops and $25.00 for the gasket. Also have some trans pan screws available as one of ours snapped when we were reinstalling it, didn't even get to torque it. As for yours, as long as the level is correct you should be good to go, IMO.
My theory on why we weren't able to get 3qts is the shape of the pan. Look at the picture of my pan, it looks like the drain plug is located at the shallowest area of the pan. Perhaps there are several versions of the pan, idk? Again, this is just my theory, I am sure 2001LC knows more and can chime in and explain.
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@2001LC is providing details for full system flush- but looks like you are just doing drain and fill which is fine- level check process is the same for either.
So what to do now that you drained 2qts and refilled 2qts.
Engine running bring AT temp to 97F- if you don’t have techstream, IR gun aimed closely ( an inch or two) from the pan will suffice. Remove level check plug- is fluid coming out: none, drip, drizzle, or full stream? Add more fluid if none, dripping- 1/2 - 1qt, recheck after temps can be measured in level check range.
FYI level check plug has a bulkhead that sits higher in the pan than the actual drain plug, so draining from level check in an attempt to get more fluid out wouldn’t help. You can see from VTHlexus picture above.
good to know on the check plug. i actually did the full 12 qt flush but it seems that my initial drain of the pan is what is throwing off my numbers so i'm focusing on the drain & fill part. I will do another drain & fill this weekend and do it as cold as possible (first time i had turned the truck around in the street and pulled into my driveway - engine was under load or idling for maybe 1-2 min before drain). if i get the same result as before, then i can only assume @Vthelexus is correct and there are different pan designs that drain different amounts. truck has been driving fine since i did the fluid change.
