Worse service mistake ever!

[SteveSRT8]

Originally Posted By: TFB1
You guys sure the [censored] don't know anything about automatic transmissions...

No fluid in pan equals no hydraulic pressure & no movement, it's B/S...


Note that the fluid in the pan is only a small portion of the total fluid.

While it may be aerated there can still be fluid getting pumped depending on the design...

 

[TFB1]

Originally Posted By: SteveSRT8
Originally Posted By: TFB1
You guys sure the [censored] don't know anything about automatic transmissions...

No fluid in pan equals no hydraulic pressure & no movement, it's B/S...


Note that the fluid in the pan is only a small portion of the total fluid.

While it may be aerated there can still be fluid getting pumped depending on the design...


Well small portion or not, in 47+ years of owning vehicles I'm yet to see a automatic trans that will move the vehicle without fluid in the pan, no oil, no pressure to engage the clutches/bands, even if the converter is full...

Till some one can PROVE(none of this I think, or my neighbors, brother in law, sisters, best friend's, husband [censored]) a automatic trans can operate without fluid pressure, I'm still calling B/S...

Now if it's a manual trans would be a different story, gear on gear could care less if it has lube, will operate till it burns up...

 

[OVERKILL]

Originally Posted By: TFB1
Originally Posted By: SteveSRT8
Originally Posted By: TFB1
You guys sure the [censored] don't know anything about automatic transmissions...

No fluid in pan equals no hydraulic pressure & no movement, it's B/S...


Note that the fluid in the pan is only a small portion of the total fluid.

While it may be aerated there can still be fluid getting pumped depending on the design...


Well small portion or not, in 47+ years of owning vehicles I'm yet to see a automatic trans that will move the vehicle without fluid in the pan, no oil, no pressure to engage the clutches/bands, even if the converter is full...

Till some one can PROVE(none of this I think, or my neighbors, brother in law, sisters, best friend's, husband [censored]) a automatic trans can operate without fluid pressure, I'm still calling B/S...

Now if it's a manual trans would be a different story, gear on gear could care less if it has lube, will operate till it burns up...


I'll throw a wrench in here and say what about the new "automatic" transmissions (which are essentially just automated manuals) found in many Ford vehicles or the Honda automatics which were much more like a manual than a traditional automatic?

 

[hattaresguy]

I'm surprised modern cars would even go into gear without the transmission full. I would think the ECU that runs everything would pick up the pressure drop in the transmission and throw a fit.

 

[SteveSRT8]

Originally Posted By: TFB1
Originally Posted By: SteveSRT8
Originally Posted By: TFB1
You guys sure the [censored] don't know anything about automatic transmissions...

No fluid in pan equals no hydraulic pressure & no movement, it's B/S...


Note that the fluid in the pan is only a small portion of the total fluid.

While it may be aerated there can still be fluid getting pumped depending on the design...




Well small portion or not, in 47+ years of owning vehicles I'm yet to see a automatic trans that will move the vehicle without fluid in the pan, no oil, no pressure to engage the clutches/bands, even if the converter is full...

Till some one can PROVE(none of this I think, or my neighbors, brother in law, sisters, best friend's, husband [censored]) a automatic trans can operate without fluid pressure, I'm still calling B/S...

Now if it's a manual trans would be a different story, gear on gear could care less if it has lube, will operate till it burns up...


You may call it whatever you want, but when a typical slushbox has 16 or even more quarts of fluid in it yet the pan holds 4 or less you may want to think about it for a minute. The majority of the fluid is still present, the pump is self priming, etc. i am not saying this is good for it, just that it can indeed move.

I have driven vehicles in fleet use with broken trans lines. They run until at least 50-75% of the fluid is expelled, then they buck, shudder and you stop. But since designs vary wildly they do not all behave the exact same way.

No baloney, my personal Silverado broke a line once with my Wife at the wheel. She called from the side of the road. After I repaired it with a bit of fuel line hose and some clamps it took almost 8 quarts, yet the pan holds just 4. This is not terribly uncommon...

 

[TFB1]

Originally Posted By: SteveSRT8

You may call it whatever you want, but when a typical slushbox has 16 or even more quarts of fluid in it yet the pan holds 4 or less you may want to think about it for a minute. The majority of the fluid is still present, the pump is self priming, etc. i am not saying this is good for it, just that it can indeed move.



With no fluid in the pan there is nothing to draw from, I don't care how much fluid is in the pump, converter, valvebody etc... What little is in the pump(maybe a tea cup) will be pumped back to the pan and there won't be enough to circulate... Possibly at speed the fluid from the converter will be forced back to the pan and it operate herky jerky, but story says drained... I'm not believing the vehicle could move unless they revved the snot out of it(and really don't believe it then), in that case they got what they deserved...

 

[CBR.worm]

I can assure you without a doubt, from personal experience, that a 4spd auto Tundra with an empty transmission pan still engages gears quite normally - much to my surprise.

That should be its own service nightmare, but no permanent damage was done - or at least not that surfaced in the next 150k or so miles.

 

[yonyon]

Originally Posted By: TFB1
I'm not believing the vehicle could move unless they revved the snot out of it(and really don't believe it then), in that case they got what they deserved...


Hypothetically, no, the trans won't work after being drained of fluid. Practically, most can. The engine starts, the pump pumps, and the pickup gets first air, then ATF, then ATF with bubbles in it. Where did the pump get ATF from after the pan drained? When it picked up air it made bubbles that displaced fluid. Yes, the pan was drained, but after running the engine for a few seconds it is no longer empty.

In practice, you now have an auto trans with fluid, but aerated fluid. This is not good for it, but at low power demands it will continue to operate. The driver who "revved the snot out of it" would not go from a non-operating trans to an operating trans, but instead go from a trans that seems to be working to one that slips. The higher revs pick up more air and come along with greater throttle opening and greater torque -> slipping and/or engagement malfunction.

Not every automatic trans will operate after being drained of fluid. There are those that will pick up a load of air and then churn away to no effect.

 

[hypervish]

Originally Posted By: friendly_jacek

http://www.reddit.com/r/Justrolledintotheshop/


Poor RX300

 

[artificialist]

Originally Posted By: hypervish
Originally Posted By: friendly_jacek

http://www.reddit.com/r/Justrolledintotheshop/


Poor RX300

Even the best mechanic can end up in this situation.

I don't know how many times I was stuck using a lift that didn't function correctly, and nobody would maintain them correctly. I met many people who were stuck in the same situation.

Just another reason I am half glad to be sidelined with medical issues.

 

[SteveSRT8]

Originally Posted By: CBR.worm
I can assure you without a doubt, from personal experience, that a 4spd auto Tundra with an empty transmission pan still engages gears quite normally - much to my surprise.

That should be its own service nightmare, but no permanent damage was done - or at least not that surfaced in the next 150k or so miles.


Same with my Silverado. Still running today and shifts fine despite pumping more than half its fluid out on the road and being driven to the point that it would no longer move.

TFB1, you may wish to note that is a LOT more than the 4 quarts available to "drain" by dropping the pan.

There are too many variables in slushbox designs to simply state flatly that they won't do this or that. You must take this into account before simply making blanket suppositions...

 

[Corvette Owner]

Originally Posted By: TFB1
Originally Posted By: Corvette Owner
I read that someone took their car in for an oil change, and the place unknowingly drained their automatic transmission oil instead. Then they added oil to already full oil pan (without checking oil level afterwards).

The person didn't get far, both transmission burned up and engine broke!

True story.


I call B/S, a automatic trans won't move the vehicle without fluid in the pan...


There is a lot of trans fluid left in the trans, like 50% in some cars.

 

[Jarlaxle]

Originally Posted By: 01rangerxl
Originally Posted By: Jarlaxle

Actually, D-M probably WAS the right fluid (or at least, an acceptable one) for the trans. IIRC, the 4-Runner from the 80's until a few years ago used the Aisin-Warner AW-4 trans (as used in Cherokees). Those do, in fact, use Dexron.


It probably was an acceptable fluid to use, but T-IV is what was likely drained out, and putting T-IV back in would have been the honest thing to do. The rule at this place though was admit to nothing and get out of screw ups the cheapest way possible.


No idea what year that 4Runner was, but my friend's Toyota truck actually calls for Dexron.

 

[Jarlaxle]

Originally Posted By: SteveSRT8
Originally Posted By: CBR.worm
I can assure you without a doubt, from personal experience, that a 4spd auto Tundra with an empty transmission pan still engages gears quite normally - much to my surprise.

That should be its own service nightmare, but no permanent damage was done - or at least not that surfaced in the next 150k or so miles.


Same with my Silverado. Still running today and shifts fine despite pumping more than half its fluid out on the road and being driven to the point that it would no longer move.

TFB1, you may wish to note that is a LOT more than the 4 quarts available to "drain" by dropping the pan.

There are too many variables in slushbox designs to simply state flatly that they won't do this or that. You must take this into account before simply making blanket suppositions...


I saw an AT545 Allison able to engage with an empty pan...I drove it ~100 yards so the tow jockey could lift the vehicle from behind. IIRC, a pan drop requires adding ~5 quarts...and an empty AT545 takes approximately five GALLONS. (The MT643 in my Genesis takes, IIRC, 23 quarts including the huge cooler.)

 

[SwampSurvivor]

Originally Posted By: Jarlaxle
Originally Posted By: SteveSRT8
Originally Posted By: CBR.worm
I can assure you without a doubt, from personal experience, that a 4spd auto Tundra with an empty transmission pan still engages gears quite normally - much to my surprise.

That should be its own service nightmare, but no permanent damage was done - or at least not that surfaced in the next 150k or so miles.


Same with my Silverado. Still running today and shifts fine despite pumping more than half its fluid out on the road and being driven to the point that it would no longer move.

TFB1, you may wish to note that is a LOT more than the 4 quarts available to "drain" by dropping the pan.

There are too many variables in slushbox designs to simply state flatly that they won't do this or that. You must take this into account before simply making blanket suppositions...


I saw an AT545 Allison able to engage with an empty pan...I drove it ~100 yards so the tow jockey could lift the vehicle from behind. IIRC, a pan drop requires adding ~5 quarts...and an empty AT545 takes approximately five GALLONS. (The MT643 in my Genesis takes, IIRC, 23 quarts including the huge cooler.)


A bit of a bump here, but my Cherokee managed to pop off a transmission cooler line while sitting at a stoplight. Luckily, it was about 1/4 mile from where I lived at the time and down hill. I just shut it off and coasted into my parking lot.

I ended up putting in nearly 1.5 gallons of fluid. It only takes 8 total.

Happened to notice a big stream of something running down the road and got out to check. Trans fluid. It didn't pump it out all at once - there was a steady stream of it behind me for a block or two.