logic behind no trans dipstick?

[Kira]

I am so disbelieving of "rag lint" being introduced via the dipstick.

You wipe off the shiny metal blade which still is lubed a bit. Where does the rag even snag?

Microscopic bits at best. The pieces of cigarette filter smokers inhale are likely bigger.

 

[Lolvoguy]

Originally Posted by Astro14
Originally Posted by Lolvoguy
Originally Posted by Sam_Julier
I keep a can of compressed air handy when doing an AT fluid flush. Before inserting the the dipstick it gets a shot of air.

Sam

I put on my favorite Johnny Cash album and dance a two-step jig before attempting any repairs/maintenance.
Been successful at keeping my cars on the road for several years.

I think Sam is keeping lint and dust off the dipstick so that it's not introduced to the transmission.

If more mechanics, both amateur and professional, had his level of care in their work, OEMs wouldn't have needed to seal transmissions.

I sincerely hope you aren't insinuating my method is any less effective.

 

[edyvw]

Once a week there is a topic about trans. dipstick.

 

[kschachn]

Originally Posted by JimPghPA
My understanding is that one of the big things that degrades fluids is exposure to air, and the very small amount of moisture that condenses out of the air and into the fluid. Over time that can add up to a lot of oxidation and moisture. When you have a dip-stick every time you go up or down a mountain, or the barometric pressure changes a small amount of air moves in or out of the air space above the fluid in your trany. When it moves in it carries new oxygen and water molecules (moisture). Some of that interacts. A sealed system does not have the fluid degrade anywhere near as fast.

I have seen some engineering specifications for some fluids and there useful life that specified different life expectancy for use in sealed and unsealed systems.

So these sealed transmissions don't have a vent either?

 

[flinter]

This still doesn't answer this question.....

How would one know if the trans drain and fill or flush service was actually done if the customer has no way of checking it WITHOUT a dipstick??

 

[edyvw]

Originally Posted by flinter
This still doesn't answer this question.....

How would one know if the trans drain and fill or flush service was actually done if the customer has no way of checking it WITHOUT a dipstick??

You take it to trusted mechanic. How many customers know where transmission dipstick is? How many customers know color difference?

 

[Wolf359]

Originally Posted by flinter
This still doesn't answer this question.....

How would one know if the trans drain and fill or flush service was actually done if the customer has no way of checking it WITHOUT a dipstick??


You've got to trust them or take it to a small indy where you can see it being done. Or ask for the video. The MB dealer has a video feed of each service bay. Never really asked about it, but it was there behind the service writer. Maybe that was just to see if the car was done or not.

 

[supton]

Originally Posted by flinter
This still doesn't answer this question.....

How would one know if the trans drain and fill or flush service was actually done if the customer has no way of checking it WITHOUT a dipstick??

Does one need to check? How does one know the oil in the diffs was changed, or the engine oil, or spark plugs, or brake fluid, or whatever? I get it, those items can be verified (to a degree--some of those fluids come out at the same color as going in, when they are changed before "being used up").

*

I'm a bit dubious on the rag lint--not saying it's a lie, I think I've heard the same story before. I'm just dubious. Many transmissions have a filter. Some are strainers, some are true filters, not sure if any fall between... The two I have are strainers and thus lint would go through them. Now I do believe that crud in the valve body would cause problems, and that the same amount of lint introduced into the engine would be completely ignored as I don't think the engine has the same sorts of fine tolerance areas that would care (might cause a bit of accelerated wear but it'd be wiped out in short order). I just don't get how that much lint could get in there...

I could buy the notion that OEM's simply looked at the data customers were providing: many (most?) never changed fluid yet were getting 150k or so between transmission failures (if ever). Those doing frequent changes yet still having failures proved that frequent fluid changes didn't matter, so to some degree I think they could sort out if fluid changes mattered or not.

 

[Astro14]

Originally Posted by Lolvoguy
Originally Posted by Astro14
Originally Posted by Lolvoguy
Originally Posted by Sam_Julier
I keep a can of compressed air handy when doing an AT fluid flush. Before inserting the the dipstick it gets a shot of air.

Sam

I put on my favorite Johnny Cash album and dance a two-step jig before attempting any repairs/maintenance.
Been successful at keeping my cars on the road for several years.

I think Sam is keeping lint and dust off the dipstick so that it's not introduced to the transmission.

If more mechanics, both amateur and professional, had his level of care in their work, OEMs wouldn't have needed to seal transmissions.

I sincerely hope you aren't insinuating my method is any less effective.

It's hard to fault your method, particularly when you choose Johnny Cash, though for difficult and challenging jobs, I prefer Warren Zevon...

 

[sloinker]

Well, he went down to dinner in his Sunday best
Excitable boy, they all said
And he rubbed the pot roast all over his chest
Excitable boy, they all said
Well, he's just an excitable boy
He took in the four a.m. show at the Clark
Excitable boy, they all said
And he bit the usherette's leg in the dark
Excitable boy, they all said
Well, he's just an excitable boy

 

[JamesBond]

to sell more cars and make maximize profit

 

[IMSA_Racing_Fan]

LOL good point! Last I heard transmissions aren't nitrogen charged. Sure are lots of excuse makers in any topic that questions manufacturers huh?
"It's because sloppy mechanics red rag lint" as if there are no filters in automatic transmissions.
"It"s because moisture going past dipstick" as if dipsticks can't have o-rings.
Many such cases.

 

[JeffKeryk]

It boggles the mind. Sealed? They have drain and fill ports. At least the Toyotas and Hondas I fool around with do.
The Toylettas uses the straw to determine the top of the fluid.
A dipstick also determines the top of the fluid.
Call me crazy, but the top of the fluid is the top of the fluid.

And they want a specific temperature.
Then there should be a specific temperature readout display.

Lifetime fluid my ....
There is no logic. Only makes it harder to check and service.
Saving a few dollars at manufacture pales compared to the time to check before delivery.
There is no logic.

Manufacturers need to learn to code. Then software could give you an easy, precise answer.

 

[nascarnation]

Filling the transmission circuit as part of the assembly line process is just another annoying process step with potential for oil spills.
The transmission can be filled as part of the transmission build and test process to compensate for the volume of oil in the vehicle external lines and cooler. It uses quick connect fittings that retain the oil in the transmission during shipping.

At GM, the first one like this was the 4T40 in the later 90s.

Plus: Easier line build, consistent quality, cost savings.
Minus: More difficult to maintain.

 

[vavavroom]

Originally Posted by JimPghPA
My understanding is that one of the big things that degrades fluids is exposure to air, and the very small amount of moisture that condenses out of the air and into the fluid. Over time that can add up to a lot of oxidation and moisture. When you have a dip-stick every time you go up or down a mountain, or the barometric pressure changes a small amount of air moves in or out of the air space above the fluid in your trany. When it moves in it carries new oxygen and water molecules (moisture). Some of that interacts. A sealed system does not have the fluid degrade anywhere near as fast.

I have seen some engineering specifications for some fluids and there useful life that specified different life expectancy for use in sealed and unsealed systems.


Even if a transmission is sealed, it still needs to be vented to allow for equalizing pressure differentials. Also, unless a transmission were completely filled with fluid or with a noble gas instead of air, condensation would still happen due to temperature fluctuations. Sealed does not mean hermetically sealed but rather it means inaccessible.

 

[vavavroom]

Originally Posted by Astro14
Because in the analysis of numerous transmission failures at GM, rag lint was found contaminating the valve body and causing the failure.

Whether professional or amateur mechanics were that careless doesn't matter. Careless mechanics caused failures and warranty claims.

It was decided that non-serviceable transmissions were less likely to have warranty claims.


I thought lint-free rags were commonly in use. I guess some folks recycle their wive's angora sweaters.

 

[Eddie]

For the typical daily driver if it is "sealed" then "don't be concerned" Most of us on this site know the fluid can be changed with some effort. Maybe the manufactures have had too much warranty work due to people putting the wrong fluid or additives in that mess the AT up? Ed

 

[IMSA_Racing_Fan]

Think about how much more fun it is to lay on your back pumping endless quarts of ATF with a plastic screw-on pump when the hose pops off or slips out and fluid splashes on your face.

 

[Snagglefoot]

The average length of time a vehicle is on the road is 11.4 years, but the average time a person keeps a new vehicle is six years. The auto makers don't care about the subsequent owners. We are the exemption regarding people who check their transmission fluid. Most don't and are totally not interested in it. In fact, I'll bet most vehicle owners have never pulled out a transmission dip stick. The car makers know this. Really, the reason to check the transmission dipstick is to make sure the fluid has not leaked out and to take a look at its condition. Since most automakers now allow 100,000 mile + intervals on the transmission fluid they don't feel the owner needs to see it.

 

[HemiBenny]

Originally Posted by flinter
This still doesn't answer this question.....

How would one know if the trans drain and fill or flush service was actually done if the customer has no way of checking it WITHOUT a dipstick??


Well you could tell by getting under the car and looking for the shiny surface that had to be cleaned after the fluid was drained out, it's gonna leave a little mess no matter how careful. The size of the mess is questionable, but you'll be able to tell if it was done. Now, did they put the correct amount back in? Did they put the proper fluid back in? Did they seal it back up correctly? Time will definitely give you the answers to those three questions.