User Panel
User Panel
User Panel
|
Posted: 9/5/2024 10:51:16 PM EST
Related to my other thread on safe levels on the dipstick...kinda.
After becoming a certified Youtube mechanic  ... I went down the rabbit hole about fluid levels in transmissions. Specifically my Honda Odyssey....There are several sites out there that say if I drain the transmission fluid by removing the drain plug...I am only actually draining about ONE THIRD of the total transmission fluid. Therefor, a single transmission fluid change will only effectively get 1/3 of the total fluid out. Then they say... if I do that change...then run it for a short time (example.. 100 miles) to mix the new with the old fluid...then change it AGAIN, I am technically only removing another 1/3 of the new/old mixed tranny fluid....and on and on... I call BS  Am I wrong? 
|
|
|
|
Posted: 9/5/2024 10:54:30 PM EST
[#1]
Yes, you're wrong.
|
|
|
|
Posted: 9/5/2024 10:54:39 PM EST
[#2]
Quoted: Related to my other thread on safe levels on the dipstick...kinda. After becoming a certified Youtube mechanic ... I went down the rabbit hole about fluid levels in transmissions. Specifically my Honda Odyssey....There are several sites out there that say if I drain the transmission fluid by removing the drain plug...I am only actually draining about ONE THIRD of the total transmission fluid. Therefor, a single transmission fluid change will only effectively get 1/3 of the total fluid out. Then they say... if I do that change...then run it for a short time (example.. 100 miles) to mix the new with the old fluid...then change it AGAIN, I am technically only removing another 1/3 of the new/old mixed tranny fluid....and on and on... I call BS Am I wrong? You're probably wrong. I don't know about the odyssey specifically, but Honda has other vehicles like that. Look at the spec of the full fluid capacity of the transmission, and compare it to how much you drain out. The Honda dealership near me will (once you're out of warranty) push a tranny flush for that reason, but the one person I know who took them up on the flush had their tranny (unsurprisingly) die shortly thereafter. They fought with Honda corporate for a while and eventually got the dealership to cover a new tranny, but still... don't do the flush. |
|
|
|
Posted: 9/5/2024 10:55:35 PM EST
[#3]
Torque converters hold a good amount of volume.
|
|
|
|
Posted: 9/5/2024 10:56:42 PM EST
[#4]
Trade in that Honda for something Nissan with a "CVT" transmission. They never need service and run forever.
|
|
|
|
Posted: 9/5/2024 10:58:04 PM EST
[#5]
Agree with the replies given, a simple drain will only get a partial amount,
|
|
|
|
Posted: 9/5/2024 10:58:12 PM EST
[#6]
Quote HistoryQuoted: You're probably wrong. I don't know about the odyssey specifically, but Honda has other vehicles like that. Look at the spec of the full fluid capacity of the transmission, and compare it to how much you drain out. The Honda dealership near me will (once you're out of warranty) push a tranny flush for that reason, but the one person I know who took them up on the flush had their tranny (unsurprisingly) die shortly thereafter. They fought with Honda corporate for a while and eventually got the dealership to cover a new tranny, but still... don't do the flush. DO NOT FLUSH A HONDA TRANSMISSION! Drain and refill trans every 30k miles and you will be good if it is the older 6 speed. The new 9 speed is every 60k miles. |
|
|
|
Posted: 9/5/2024 11:00:20 PM EST
[#7]
Just about every auto trans on the planet has roughly 10-12 liters. The most you can drain, even if you remove the pan, is roughly 5 to 6 liters.
Use that information as you will. |
|
|
|
Posted: 9/5/2024 11:01:10 PM EST
[#8]
I don't pretend to understand auto trans, but yeah, there is a lot that doesn't drain by gravity. Not a simple diff in other words. Just look at pics of them in pieces.
|
|
|
|
Posted: 9/5/2024 11:04:44 PM EST
[#9]
Yeah, between the converter, cooler, valve body and the clutch drums, you are only getting a bit over a 1/3 dropping the pan..
|
|
|
|
Posted: 9/5/2024 11:04:58 PM EST
[#10]
You’re wrong, sorry.
On Hondas that I’ve personally maintained that had the ~3qt drain and fill, I just did it at every other oil change. There’s no way to get all the oil out. So if you change it, you’re only changing 1/3 of the oil. If you do it again in 100 miles, you’re changing 1/3 new oil, 2/3 old oil. No way to ever really change it all. |
|
|
|
Posted: 9/5/2024 11:08:09 PM EST
[#11]
Quote HistoryQuoted: Yes, you're wrong. This. I call it the replacement by dilution method. It's how I change tranny fluid. |
|
|
|
Posted: 9/5/2024 11:09:54 PM EST
[#12]
Quote HistoryQuoted: Yes, you're wrong. |
|
|
|
Posted: 9/5/2024 11:11:54 PM EST
[#13]
Quote HistoryQuoted: Yes, you're wrong. |
|
|
|
Posted: 9/5/2024 11:15:14 PM EST
[#14]
There is tranny fluid in the cooler as well as the valve body also. Best solution is a tranny flush and fill.
|
|
|
|
Posted: 9/5/2024 11:18:09 PM EST
[#15]
For an automatic transmission, yes.
|
|
|
|
Posted: 9/5/2024 11:20:57 PM EST
[#16]
Yes, you're wrong.
Several drain and fills is the accepted easy way to refresh damaged trans oil, to avoid the potential harm of a forced pressure "flush". The only other acceptable way to refresh fluid is to collect fluid that is pumped out from the trans going to the cooler, while putting in fresh fluid, a couple quarts at a time, until the fluid exiting runs clear/fresh.  Toyota/Lexus Sealed (No Dipstick) Automatic Transmission Flush (Fluid Exchange) |
|
|
|
Posted: 9/5/2024 11:22:22 PM EST
[#17]
Quote HistoryQuoted: No way to ever really change it all. I've seen people disconnect the hose to the transmission cooler, let the tranny squirt out the old fluid, and have a second guy pouring new fluid in about as fast as it came out. I'm not sure I'd try it, but it seemed to do a good job getting most of it changed. |
|
|
|
Posted: 9/5/2024 11:22:25 PM EST
[#18]
Quote HistoryQuoted: Trade in that Honda for something Nissan with a "CVT" transmission. They never need service and run forever. 
|
|
|
|
Posted: 9/5/2024 11:23:53 PM EST
[#19]
Congratulations! You're in the right place.
GD is THE internet spot for questions about Trannys! |
|
|
|
Posted: 9/5/2024 11:28:05 PM EST
[#20]
Quote HistoryQuoted: I've seen people disconnect the hose to the transmission cooler, let the tranny squirt out the old fluid, and have a second guy pouring new fluid in about as fast as it came out. I'm not sure I'd try it, but it seemed to do a good job getting most of it changed. See the video above. It's pretty safe if you go just a couple quarts at a time. |
|
|
|
Posted: 9/5/2024 11:29:02 PM EST
[#21]
Quote HistoryQuoted: Congratulations! You're in the right place. GD is THE internet spot for questions about Trannys! |
|
|
|
Posted: 9/5/2024 11:50:30 PM EST
[#22]
I use this same process with radiators and antifreeze.
|
|
|
|
Posted: 9/5/2024 11:57:32 PM EST
[#23]
Drain, fill, drive, repeat until fluid looks nice and red.
|
|
|
|
Posted: 9/6/2024 12:01:17 AM EST
[#24]
Quoted: Related to my other thread on safe levels on the dipstick...kinda. After becoming a certified Youtube mechanic ... I went down the rabbit hole about fluid levels in transmissions. Specifically my Honda Odyssey....There are several sites out there that say if I drain the transmission fluid by removing the drain plug...I am only actually draining about ONE THIRD of the total transmission fluid. Therefor, a single transmission fluid change will only effectively get 1/3 of the total fluid out. I call BS Am I wrong? You don't have to go 100 miles. The last one I did I dropped the pan, changed the filter, and refilled. With the rear off the ground I ran it through all the gears for like a minute or two and repeated (less the pan drop and filter replacement) until I went through 18 quarts. I didn't feel like dealing with a larger mess of removing a cooler line and doing a fluid exchange again. |
|
|
|
Posted: 9/6/2024 12:49:03 AM EST
[#25]
31 yrs working in shops
The last 8 years I've seen fewer Techs doing flushes with those bg machines or kastle trans flush machines on trains Especially higher mileage trans missions 100k etc Use to buy these type of containers and whatever came out was put back in when the pan was removed  Same thing fir power steering pumps Oil out the cooler hose into container Reconnect hose Refill Repeat til close to clean color |
|
|
|
Posted: 9/6/2024 2:39:49 AM EST
[#26]
Definitely wrong. Look up your capacity then pull the plug. You’ll be short
|
|
|
|
Posted: 9/6/2024 3:18:08 AM EST
[#27]
Quoted: Related to my other thread on safe levels on the dipstick...kinda. After becoming a certified Youtube mechanic ... I went down the rabbit hole about fluid levels in transmissions. Specifically my Honda Odyssey....There are several sites out there that say if I drain the transmission fluid by removing the drain plug...I am only actually draining about ONE THIRD of the total transmission fluid. Therefor, a single transmission fluid change will only effectively get 1/3 of the total fluid out. Then they say... if I do that change...then run it for a short time (example.. 100 miles) to mix the new with the old fluid...then change it AGAIN, I am technically only removing another 1/3 of the new/old mixed tranny fluid....and on and on... I call BS Am I wrong? Some heavy duty torque converters have a drain plug in them to get as much out in one drain. That's where a large majority of your fluid is inside a transmission. |
|
|
|
Posted: 9/6/2024 3:19:47 AM EST
[#28]
Quote HistoryQuoted: 31 yrs working in shops The last 8 years I've seen fewer Techs doing flushes with those bg machines or kastle trans flush machines on trains Especially higher mileage trans missions 100k etc Use to buy these type of containers and whatever came out was put back in when the pan was removed https://cdn11.bigcommerce.com/s-raxt2z29l9/images/stencil/850x850/products/306125/277019/1b9a1f87-ad9d-4ddc-8663-01d80ebb5c14__98770.1722479431.png?c=1 Same thing fir power steering pumps Oil out the cooler hose into container Reconnect hose Refill Repeat til close to clean color Legit. Flat rate with these dipstick less transmissions? Get fucked with your bullshit factory method when th dash lights or the scan tool. What I measure coming out is going back in with a schosh extra. |
|
|
|
Posted: 9/6/2024 3:22:20 AM EST
[#29]
Quoted: Am I wrong? 
|
|
|
|
Posted: 9/6/2024 4:58:25 AM EST
[#30]
Quote HistoryQuoted: Torque converters hold a good amount of volume. Yep, OP is wrong. |
|
|
|
Posted: 9/6/2024 5:46:44 AM EST
[#31]
The new f550 I was assigned at work does not have a trans dip stick.
|
|
|
|
Posted: 9/6/2024 5:52:49 AM EST
[#32]
Leave the plug out and run it around the block until it holds more.
|
|
|
|
Posted: 9/6/2024 8:26:25 AM EST
[#33]
Quoted: Related to my other thread on safe levels on the dipstick...kinda. After becoming a certified Youtube mechanic ... I went down the rabbit hole about fluid levels in transmissions. Specifically my Honda Odyssey....There are several sites out there that say if I drain the transmission fluid by removing the drain plug...I am only actually draining about ONE THIRD of the total transmission fluid. Therefor, a single transmission fluid change will only effectively get 1/3 of the total fluid out. Then they say... if I do that change...then run it for a short time (example.. 100 miles) to mix the new with the old fluid...then change it AGAIN, I am technically only removing another 1/3 of the new/old mixed tranny fluid....and on and on... I call BS Am I wrong? The math has been done on this. You are wrong. You didn't say what year Odyssey. A typical 6-speed transmission used in these has a total capacity of 8 quarts (depending on year model). A change is between 3.4 and 3.6 quarts using the drain and fill method. When you make the first drain/fill, you are removing 100% old fluid, so we will say 3.5 quarts. The fluid is now 44% new fluid, and 56% old. When you make the second change, you are draining out 3.5 quarts of fluid, but only 1.86 quarts of "old" fluid by percentage. The fluid is now 68% new fluid, 32% old after 2 changes. When you make the third change, you are draining out 1.12 quarts of "old" fluid by percentage. The fluid is now 82% new fluid, 18% old fluid after 3 changes. When you make the 4th change, you are draining out 0.63 quarts of "old" fluid by percentage. The fluid is now 90% new fluid, 10% old fluid after 4 changes. Most Honda owners when doing a Honda factory recommended "flush" make 3 drain and fill changes, which changes out around 80% of the fluid. When I switched my Honda over to Valvoline Maxlife, I did 3 changes with 10-20 miles of driving between each change. If Maxlife ATF was not so compatible with DW-1, I would have done a 4th change to get closer to 90%. Honda does not recommend any kind of aftermarket flush procedure, drain and fills only. It is so damned easy to perform this, most Honda owners that DIY oil changes, do a transmission fluid change every second or third oil change depending on their OCI. |
|
|
|
Posted: 9/6/2024 8:37:48 AM EST
[#34]
Yeah you’re wrong. That’s why for the six speed trans Honda had the bulletin to reprogram the TCM and drain and fill the fluid three times, running through all the gears between all three flushes when people were getting bad judders.
|
|
|
|
Posted: 9/6/2024 8:59:28 AM EST
[#35]
Quote HistoryQuoted: DO NOT FLUSH A HONDA TRANSMISSION! Drain and refill trans every 30k miles and you will be good if it is the older 6 speed. The new 9 speed is every 60k miles. Quote HistoryQuoted: Quoted: You're probably wrong. I don't know about the odyssey specifically, but Honda has other vehicles like that. Look at the spec of the full fluid capacity of the transmission, and compare it to how much you drain out. The Honda dealership near me will (once you're out of warranty) push a tranny flush for that reason, but the one person I know who took them up on the flush had their tranny (unsurprisingly) die shortly thereafter. They fought with Honda corporate for a while and eventually got the dealership to cover a new tranny, but still... don't do the flush. DO NOT FLUSH A HONDA TRANSMISSION! Drain and refill trans every 30k miles and you will be good if it is the older 6 speed. The new 9 speed is every 60k miles. THIS! I do a 'spill and fill' (4 qts come out and 4 go in) every third oil change. Something about Honda trannys are just not that robust. Someone (not me) did the math and after the third Spill and Fill you've replaced like 90%+ of the old fluid. If you do it on a regular basis just do it every 3-4 oil changes. IF doing it for the first time, do 3 in a row with some driving in between to get a 'fresh' start. ETA: It appears the Oddy carries about 7.4 qts of fluid, drain and refill 4 qts will get you to the top of the 'full' on the dipstick, so it appears for a spill and fill you're replacing about 50%. Someone may come in and correct me. |
|
|
|
Posted: 9/6/2024 9:05:36 AM EST
[#36]
Quote HistoryQuoted: ETA: It appears the Oddy carries about 7.4 qts of fluid, drain and refill 4 qts will get you to the top of the 'full' on the dipstick, so it appears for a spill and fill you're replacing about 50%. Someone may come in and correct me. 6 speed? 9 speed? newer 10 speed? Capacities and drain/fill amount are all different (as are the fluids required) |
|
|
|
Posted: 9/6/2024 9:06:49 AM EST
[#37]
Yes that is correct.
I prefer to just drop the fluid in the pan every 30k. You'll never have perfectly clean transmission oil but it will always be decently fresh. Same with coolant. |
|
|
|
Posted: 9/6/2024 9:07:07 AM EST
[#38]
Tag
|
|
|
|
Posted: 9/6/2024 9:07:17 AM EST
[#39]
Quote HistoryQuoted: Trade in that Honda for something Nissan with a "CVT" transmission. They never need service and run forever. He's got JOKES people! Jokes! |
|
|
|
Posted: 9/6/2024 9:09:00 AM EST
[#40]
You’ve never been more wrong
Well maybe, but this is about as wrong as you can get |
|
|
|
Posted: 9/6/2024 9:09:16 AM EST
[#41]
Quote HistoryQuoted: Yes that is correct. I prefer to just drop the fluid in the pan every 30k. Please show us all where the pan is on a Honda Odyssey transmission like the OP has? |
|
|
|
Posted: 9/6/2024 9:10:28 AM EST
[#42]
Damn I've know this since I was a kid
|
|
|
|
Posted: 9/6/2024 9:11:57 AM EST
[#43]
Quote History[b]Originally Posted By GoGo Trade in that Honda for something Nissan with a "CVT" transmission. They never need service and run forever. “For the life of the transmission.” |
|
|
|
Posted: 9/6/2024 9:15:03 AM EST
[#44]
Here's a spreadsheet I found online that'll help you calculate the percentage of new fluid when you do a trans fluid swap:
https://www.dropbox.com/scl/fi/szyby3o291efqh34a3zxl/Partial-Drain-Helper.xlsx And the original discussion on the topic: https://bobistheoilguy.com/forums/threads/transmission-partial-drain-calculator-sticky.215133/ |
|
|
|
Posted: 9/6/2024 9:16:40 AM EST
[#45]
We've had a 2000 accord since about 2003 or so. When it was at about 90k miles, mechanic who replaced timing belt highly recommended I do a transmission flush. Transmission was already exhibiting really rough 1st to second gear shifts. I used Honda fluid, drained and replaced fluid after a few days of running 2 or 3 times. Now, transmission still has same hard shift. Well over 200k miles on car. But shifting has not gotten worse. I credit the flush. Car is no longer driven. But still 100% reliable. We are probably going to give it to family member soon.
|
|
|
|
Posted: 9/6/2024 9:18:39 AM EST
[#46]
Quote HistoryQuoted: The math has been done on this. You are wrong. You didn't say what year Odyssey. A typical 6-speed transmission used in these has a total capacity of 8 quarts (depending on year model). A change is between 3.4 and 3.6 quarts using the drain and fill method. When you make the first drain/fill, you are removing 100% old fluid, so we will say 3.5 quarts. The fluid is now 44% new fluid, and 56% old. When you make the second change, you are draining out 3.5 quarts of fluid, but only 1.86 quarts of "old" fluid by percentage. The fluid is now 68% new fluid, 32% old after 2 changes. When you make the third change, you are draining out 1.12 quarts of "old" fluid by percentage. The fluid is now 82% new fluid, 18% old fluid after 3 changes. When you make the 4th change, you are draining out 0.63 quarts of "old" fluid by percentage. The fluid is now 90% new fluid, 10% old fluid after 4 changes. Most Honda owners when doing a Honda factory recommended "flush" make 3 drain and fill changes, which changes out around 80% of the fluid. When I switched my Honda over to Valvoline Maxlife, I did 3 changes with 10-20 miles of driving between each change. If Maxlife ATF was not so compatible with DW-1, I would have done a 4th change to get closer to 90%. Honda does not recommend any kind of aftermarket flush procedure, drain and fills only. It is so damned easy to perform this, most Honda owners that DIY oil changes, do a transmission fluid change every second or third oil change depending on their OCI. Honda Odyssey owner, tech school instructor (auto transmisions). This is a very good explanation. |
|
|
|
Posted: 9/6/2024 9:30:39 AM EST
[#47]
One of the stupid features of the CVT in my Altima coupe was the drain plug located 4 or 5 inches, maybe 6, from the bottom of the transmission.
The second was the laughable single pass cooling line through the bottom of the radiator. The third was the dip stick, its tube size, and the blocker inside to stop almost anything from entering. The second was probably the service writer. |
|
|
|
Posted: 9/6/2024 10:00:54 AM EST
[#48]
The converter holds a significant amount of the tranny fluid. To do it in one shot you can disconnect the cooler lines from the radiator. Hook the tranny intake to a supply of clean fluid and catch the output in a bucket until it runs clean. A shop should have a machine to automate this.
The other reason Honda wants you to dump 1/3 of the fluid every 30k is their transmissions (at least the older 5 speeds) lack a debris screen. |
|
|
|
Posted: 9/6/2024 10:10:23 AM EST
[#49]
Quote HistoryQuoted: Please show us all where the pan is on a Honda Odyssey transmission like the OP has? Quote HistoryQuoted: Quoted: Yes that is correct. I prefer to just drop the fluid in the pan every 30k. Please show us all where the pan is on a Honda Odyssey transmission like the OP has? Not sure. Does it not have a drain plug? |
|
|
|
Posted: 9/6/2024 10:30:29 AM EST
[#50]
Quote HistoryQuoted: You’re wrong, sorry. On Hondas that I’ve personally maintained that had the ~3qt drain and fill, I just did it at every other oil change. There’s no way to get all the oil out. So if you change it, you’re only changing 1/3 of the oil. If you do it again in 100 miles, you’re changing 1/3 new oil, 2/3 old oil. No way to ever really change it all. thats the way my 98 civic is 3qts, no filter just a screen somewhere in it they say....drian and fill a couple of times a year keeps it super clean. |
|
|
Win a FREE Membership!
Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!
You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.
AR15.COM is the world's largest firearm community and is a gathering place for firearm enthusiasts of all types.
From hunters and military members, to competition shooters and general firearm enthusiasts, we welcome anyone who values and respects the way of the firearm.
Subscribe to our monthly Newsletter to receive firearm news, product discounts from your favorite Industry Partners, and more.
Copyright © 1996-2024 AR15.COM LLC. All Rights Reserved.
Any use of this content without express written consent is prohibited.
AR15.Com reserves the right to overwrite or replace any affiliate, commercial, or monetizable links, posted by users, with our own.
