Worn-Out ATF Causes "Lack of Responsiveness?"

[The Critic]

Here's an interesting one.

I just read JMHC's thread. Supposedly, the vehicle was overdue for an ATF flush. As a result of the worn-out ATF, it caused the vehicle to exhibit a "lack of responsiveness" and poor shift quality, both of which were cured by an ATF flush.

My friend has a Corolla with 56k on the original T-IV. When I took it in for service last week, she mentioned that the shifts were clunky and the vehicle was displaying a "lack of responsiveness." She said that on the highway, the car felt slow to respond and "lacking in power."

I drove the car and didn't notice anything unusual, aside from the rather clunky shifts. After reading JMHC's thread, perhaps a "lack of responsiveness" may truly exist? This is puzzling to me. Personally, I have never seen worn-out transmission fluid cause a vehicle to exhibit a "lack of responsiveness." Is this a normal symptom of worn-out ATF?

Thanks.

 

[Hethaerto]

If the ATF is old enough to be completely worn out, I'd say it's a good bet other fluids/items are worn out, too.

 

[Falcon_LS]

Could you further define 'lack of responsiveness'? Does it hold gears for too long (possibly TPS)? Does it not downshift on demand (possibly kick down cable)? What year is this Corolla? What colour is the ATF? Does it smell burnt? Are there any additives present in the ATF?

 

[unDummy]

Low visc=lower line pressure=slower shifts=...

Worn out fluid = worn out additive package = more friction = more wear = more accumulated wear=...

Worn out additive package = less sealing of seals = more seal blowby = slower shifts = less holding power = more slippage = more wear

More suspended accumulated wear = more wear on seals and pistons = more internal leakage =.......

Worn out additive package = more varnish crud buildup = reduce flow through passages = ....

More varnish = stuck valve body and solenoids =......

A flush is worth it!

 

[wafrederick1]

Avoid a flush with the machine and do the line flush.With the line flush,you get rid of the dirt crud out and you can see the condition of the fluid.With the machine is another story,packs the dirt,crud,metal shavings and clutch material into the valve body which a valve body cleaning or a rebuild is required.

 

[TallPaul]

I only run Redline ATF in my automatic transmissions. The extra cost is more than justified in peace of mind that the fluid and additives are not going to wear out unless I am extremely negligent about maintenance.

 

[Whitewolf]

Originally Posted By: The Critic
Here's an interesting one.

I just read JMHC's thread. Supposedly, the vehicle was overdue for an ATF flush. As a result of the worn-out ATF, it caused the vehicle to exhibit a "lack of responsiveness" and poor shift quality, both of which were cured by an ATF flush.

My friend has a Corolla with 56k on the original T-IV. When I took it in for service last week, she mentioned that the shifts were clunky and the vehicle was displaying a "lack of responsiveness." She said that on the highway, the car felt slow to respond and "lacking in power."

I drove the car and didn't notice anything unusual, aside from the rather clunky shifts. After reading JMHC's thread, perhaps a "lack of responsiveness" may truly exist? This is puzzling to me. Personally, I have never seen worn-out transmission fluid cause a vehicle to exhibit a "lack of responsiveness." Is this a normal symptom of worn-out ATF?

Thanks.


It can be due to degraded anti-foam/anti-aeration performance resulting in unstable line pressure.

 

[Donald]

Originally Posted By: wafrederick1
Avoid a flush with the machine and do the line flush.With the line flush,you get rid of the dirt crud out and you can see the condition of the fluid.With the machine is another story,packs the dirt,crud,metal shavings and clutch material into the valve body which a valve body cleaning or a rebuild is required.


Your response is inaccurate and misleading. Please explain how a flush via a machine vs a cooler line flush does anything different. I would guess you are misinformed as to how a machine does the flush. Basically a machine keeps the pan full of new ATF so the transmission's own pump (key few words here) can pump it through the transmission. You could do the same by pouring ATF into the dipstick tube.

Also I do not own a shop or have any financial interest in transmission flush machines. Flush machines are 2nd best for people who do not want to do their own cooler line flush (and its easier than you think).

 

[doitmyself]

+1 to Donald's statements.

wafrederick1, no offense intended, but you consistently share wrong information here:

Chrysler approves Dexron plus Lubegard additive?
Autozone lifetime brake pad warrenty is one time only?
Ceramic pads eat rotors?

In this example, please google T-Tec transmission machine to learn the truth...."T-Tech eliminates the potential
for vehicle damage because it uses the vehicles
transmission pump to regulate the service,..."

 

[wiswind]

I do the cooler line fluid exchange on my windstar.....works very well.
I think the terms "flush" and "exchange" get used in place of each other.

Using a chemical "flush" like the motor "flush" products is not recommended for most (if not all) automatic transmissions.

Doing a fluid EXCHANGE at the recommended interval is HIGHLY recommended for those who wish to keep their vehicle for longer than the factory waranty period.

What I would stress as being super important is to take note of the recommended service interval for your particular transmission.
Mine is 30K miles for "normal" service, 21K miles for "severe" service.
That is shorter than many of us were used to with the older transmissions that, unless you abused them, you basically forgot about.....the vehicle would rust apart before you would need to worry about tranny service.

Newer transmissions need the fluid exchanged at the specified interval.
The exchange "machine" service that you want is one that simply adds new fluid as the old fluid comes out.
As I mentioned at the start.....this is often called a transmission "flush".
The fluid exchange with the machine does a nice job, costs more.....the facility needs to make money....but is well worth the cost for those who do not do it on their own.

Many folks do not have a place to work on their vehicle.....and/or do not feel confident to do it on their own.
You can almost always bring your own chosen brand of fluid for them to use, if you don't want to use their "house" brand.
Yes, as with any service, there are rip-off-joinst out there, however there are honest shops.....with great people to work with in them.
Getting the tranny fluid changed, by the time it is due, with a fluid that meets the specification that is called for by your particular vehicle, is what is important.....going to a shop with a machine, or doing it on your own is dependant upon each person's own situation.

 

[wafrederick1]

The Flush Machine does damage and i know one transmission shop in Muskegon that can prove it,Z transmission.They love making money after a flush was done with rebuilds and valve bodies.GM does not recomend flushing a transmission with the machine and it says in the factory shop manual.Honda does not either fearing transmission damage.One oil change chain was caught doing this recomending flushes.The last flush with the machine I heard was disastorious,would not shift when cold and would shift when warmed up.I did replace a transmission in a 1999 Monte carlo,acted up after a flush and tried to fix it once when did not help.I know the factory Ford shop manual shows how to do the line flush their way.The machines need to taken off the market.

 

[qship1996]

you are clueless.

 

[Donald]

Originally Posted By: wafrederick1
The Flush Machine does damage and i know one transmission shop in Muskegon that can prove it,Z transmission.They love making money after a flush was done with rebuilds and valve bodies.GM does not recomend flushing a transmission with the machine and it says in the factory shop manual.Honda does not either fearing transmission damage.One oil change chain was caught doing this recomending flushes.The last flush with the machine I heard was disastorious,would not shift when cold and would shift when warmed up.I did replace a transmission in a 1999 Monte carlo,acted up after a flush and tried to fix it once when did not help.I know the factory Ford shop manual shows how to do the line flush their way.The machines need to taken off the market.


I would assume that all the vehicles you mention were on the way out.

 

[bmwtechguy]

I think you guys that disagree are talking about 2 different types of machines. One type is a high pressure flush machine that even uses a pulsating high pressure fluid stream in the cooler lines to push fluid through and clean/flush the unit. This type of flush is risky IMO due to the crud that can get loosened up and pushed into or through the wrong places inside the unit. These types of flush machines have screwed up a lot of transmissions over the years and have given away somewhat to the safer T-tec type machines that just do a low pressure fluid exchange through the cooler lines.

 

[Donald]

Originally Posted By: bmwtechguy
I think you guys that disagree are talking about 2 different types of machines. One type is a high pressure flush machine that even uses a pulsating high pressure fluid stream in the cooler lines to push fluid through and clean/flush the unit. This type of flush is risky IMO due to the crud that can get loosened up and pushed into or through the wrong places inside the unit. These types of flush machines have screwed up a lot of transmissions over the years and have given away somewhat to the safer T-tec type machines that just do a low pressure fluid exchange through the cooler lines.


If a flush machine uses high or low pressure to push ATF into the return line the ATF just ends up in the pan, it does not go anywhere else unless the car is running and then the transmission's own pump pushes the ATF through transmission at the normal pressure regardless of the pressure of the flush machine.

If one used a flush machine to push ATF backwards through the supply line (car off) I would think the transmission's own pump would stop the flow.

Can you point to a flush machine the uses pulsating high pressure?

 

[doitmyself]

Well, we're getting way off topic here, but I too would like to see some hard evidence that these high pressure, reverse flush, pulsating machines exist. There are lots of anecdotal references to this process, but I cannot find evidence that these machines actually exist.

Anyone?

 

[RF Overlord]

Just to add fuel to the fire, my Ford service manual explicitly says that using a fluid exhange machine is the proper and recommended way to change the fluid.

I too would like to see hard evidence of these high-pressure pulsating reverse-flush machines...

 

[JMHC]

There are some major misconceptions about flush machines. First, the t-tech machines do NOT use an auxiliary pump that push anything backwards through a transmission. It's always amazes me how much info is out there indicating flushes caused transmission failures. Having had this done, they attach the machine, and have you start the car. Why? Because the machine uses the transmission's own pump to circulate fluid in the normal direction. The fluid is exchanged through the cooler lines.

Since this thread started with my post, I'll say fluid is a HUGE influence on performance. I know this because of my dad...this is the 2nd car in a row in which he did this! That last was a 1994 Mercury Grand Marquis...slipped, hesitated, etc. so he went and got a flush at 100,000 miles. Old fluid came out black as night, but after the flush, the car shifted perfect. Last time I saw the new owners, it had 140,000 on it with no issues. The Vibe was the same way. Talked to my dad the other day and the car is shifting smooth as silk after the flush.

That said I have an 07 Honda Accord V6. For some reason Honda indicates a flush is prohibited. On that one I drain and fill 3 quarts every 25K or so. Unless the manufacturer prohibits a flush, I think they're fine. It has worked well for my father...even with neglected service intervals.