Anyone service an Automatic Tranny with no dip...

[demarpaint]

I think I asked this question about a year ago, and didn't get to far with it. I want to do a fluid exchange on a Jeep that has a yellow plug in the fill tube that says dealer service only, and no dipstick. I guess it was Chrylser's way to save $3 on a vehicle and generate income for the service departments.

At any rate they have a special stick used for determining fluid level based on temperature.

I chatted with someone who is a tech and made this suggestion based on our conversation. I have a dipstick from an older Jeep that uses the same transmission. What I planned on doing was first being certain that the factory filled the unit correctly by having a friend in a shop check the level. Then I was going to calibrate my dipstick by driving for 30 minutes, taking a pan temp reading, then idling the car for 2 minutes in park, and marking my stick. [I just have to be sure Jeep automatic transmissions are checked in park and not neutral.]

Checking fluid in the future I would drive for 30 minutes, idle for 2 minutes, take a temp reading of the pan and check the fluid level when the pan was lets say +/-5*F of the reading I used to calibrate my dipstick. One other note I would check pan temps over a period of several days to see if the temps are close after a 30 minute run to be sure this idea has any merit to begin with.

Suggestions are welcome along with methods other DYI'ers have done with similar vehicles.

TIA

 

[caravanmike]

alot of manufactures are doing the sealed transmission thing. mike

 

[demarpaint]

Originally Posted By: caravanmike
alot of manufactures are doing the sealed transmission thing. mike


I know, and IMO it is not a good idea. Lets just say for the sake of argument that you're on a road trip. You notice some ATF under your car and see it is coming from your transmission pan. It's the middle of the night and you have to get home. A dipstick would tell you if your level is full or not, and you can check and add if needed. W/O the stick you are SOL.

In my case I want to service my own unit and not spend $100 for a fancy dipstick to do so. I think the method I discussed with a Bitog friend is a good way to do it.

 

[JTK]

I've done 2 dipstick-less and basically fill port-less 4L30E's. Whadda PITA. These units basically have two downward facing drain plugs on the pan. One is stamped/recessed further up than the drain and used to check level and fill. I made my own compressed air pump to fill it back up. I never worried about the tempature specs. IMO, if you drain it cold and fill it cold with the same amount of fluid you drained out, how can you go wrong. Level was always right on.

Joel

 

[demarpaint]

Originally Posted By: JTK
I never worried about the tempature specs. IMO, if you drain it cold and fill it cold with the same amount of fluid you drained out, how can you go wrong. Level was always right on.

Joel


My setup is different, since I have a fill tube as in the past, just no dipstick. You bring up an interesting point. I would imagine if the car sat overnight the fluid would seek the same level day in and day out, as long as there are no leaks. I'm almost tempted to make a cold full mark, and see if that level is always the same after an overnight stay on level ground. If it is then I'd guess I could pump out fluid, hot, then measure what I took out, and that amount less a little, and top it off cold the following morning. The Jeep can sit overnight w/o me having to use it, so topping up in the morning is no problem.

I'm just thinking outloud. I understand the hot level and cold level are different, but I would imagine that after sitting overnight the cold level should always be the same. If I'm missing something please let me know.

Thanks!

 

[finalyzd]

They do make a dipstick for diy. I was looking at one from my supplier. I believe it was 35 bucks. For the dodge chargers,chrysler 300s and jeeps I think. With the little cap that says dealer only

 

[daman]

I have done a few yes,,now on GM's there's a plug in the side of the trans down by the pan you have to jack up the car level run it a few mins then pull the plug running if fluid runs out your full, Kind of a PITA tho but works.

 

[hate2work]

Here's a nice write up with pics from a guy who did this with his Tacoma. Not sure if this would be exactly the same procedure, but you might get something from reading it.

http://www.tacomaworld.com/forum/2nd-gen-tacomas/63851-how-drain-refill-automatic-transmission.html

Also, I have read many times on diff forums that if you simply replace the exact amount you removed, that works as well. If that's what I was going to do, I would drain it cold and replace it cold, like JTK mentioned.

Good luck-

 

[dkryan]

They did us no favors with those sealed transmissions!

If you used a T-Tec machine for a cooler line flush, would you not accomplish the same thing? The downside, I guess, is you'd have to have a way to check the level to ensure it was not over- or under-filled. Hence, a trip to the dealer.

Arrrggghhhhh!

 

[hate2work]

Originally Posted By: dkryan
They did us no favors with those sealed transmissions!

If you used a T-Tec machine for a cooler line flush, would you not accomplish the same thing? The downside, I guess, is you'd have to have a way to check the level to ensure it was not over- or under-filled. Hence, a trip to the dealer.

Arrrggghhhhh!


There IS a way to check the fluid level, it's just that it's a complicated, temperature sensitive procedure that must be done under the vehicle with a plug on the transmission.

And I agree....Arrrggghhhhh!

 

[demarpaint]

Originally Posted By: hate2work
Here's a nice write up with pics from a guy who did this with his Tacoma. Not sure if this would be exactly the same procedure, but you might get something from reading it.

http://www.tacomaworld.com/forum/2nd-gen-tacomas/63851-how-drain-refill-automatic-transmission.html

Also, I have read many times on diff forums that if you simply replace the exact amount you removed, that works as well. If that's what I was going to do, I would drain it cold and replace it cold, like JTK mentioned.

Good luck-


I agree, with draining cold, measuring and adding the same amount back, but there is one glitch. If the factory filled the unit incorrectly then all bets are off. Lets assssssssume they filled it correctly, or we bite the bullet and pay someone to check the level. I want to establish with the dipstick from an older unit that fits, either a cold full level, after sitting overnight. Or a hot filled level, driving 30 minutes, two minute idle and a pan temp reading. As long at that pan reading is the same then the fluid level should be the same. Then do a cold suction drain, measure refill with the same amount and confirm with the stick.

What I fail to understand is if a car sits for lets say overnight on level ground. Isn't the cold level always going to be the same if the vehicle sits overnight on level ground? Calibrating a cold level check, and a hot level check, the way I mentioned should work, as long as the unit was properly filled from the beginning?

 

[morris]

back in stone ages, a chrysler auto trans ( after 1961 ),the aul one. you was to check trans dip stick, after you run it through all the gears, you put it in neutral not park. the reason is the cooling lines didnt run any fluid in park. iam sure they do things totaly different now days. different subject: if your chrysler aul trans bangs hard going from park to revers, take the lever all the way to low gear first, then to park. revers raises line to 350 psi, which causes it bang sometimes. low gear only to about 150 psi, this way the 150 fills the low/resvers band first. insted of filling it to 360 first. please note: my psi may be a little off, but but get the idea.

 

[demarpaint]

You're right. IRRC Chrysler AT had to be checked in Neutral. I'll have to check that out before I calibrate the dispstick I have. Either way once I calibrate it I will check it a few times over a period of a few days to be certain of the level before I swap out any fluid.

The cold level I plan on setting up will be done with the engine off after it sits overnight and is stone cold. If that level is aways the same that will make things a lot easier.

 

[cbear]

I've been looking at this because I have a Dodge Nitro with the sealed NAG1 aka W5A580 transmission. This is the one you're suppose to use a graduated dipstick with a sacn tool that reads the trans temp. From what I've read, none of the Chrysler NAG1s came with a dipstick, just the sealed tube.

I'm going to do a drain and fill, so I just got an old Ram truck dipstick and scribed the cold line. Once I get a good hot reading, I'm going to go from there. Also going to add a spin on remote filter and a drain plug kit.

From what I've read, the MB and Sprinter van NAG1s already have a drain plug as well as torque converter drain access. I do not think that is the case with the Chryslers.

 

[demarpaint]

Originally Posted By: cbear
I've been looking at this because I have a Dodge Nitro with the sealed NAG1 aka W5A580 transmission. This is the one you're suppose to use a graduated dipstick with a sacn tool that reads the trans temp. From what I've read, none of the Chrysler NAG1s came with a dipstick, just the sealed tube.

I'm going to do a drain and fill, so I just got an old Ram truck dipstick and scribed the cold line. Once I get a good hot reading, I'm going to go from there. Also going to add a spin on remote filter and a drain plug kit.

From what I've read, the MB and Sprinter van NAG1s already have a drain plug as well as torque converter drain access. I do not think that is the case with the Chryslers.


My Jeep calls for the same scan tool as your Nitro. I got a dipstick from an 06 Liberty which used the exact same transmission as the one in my 08.

What confuses me is this. If the vehicle sits overnight, shouldn't that cold level always be the same? I understand the operating hot running level can be different depending on how hot the ATF is, but the cold level should always be the same. I'd be willing to let the vehicle sit on level ground for 24 hours to check cold level. Drive and let it sit another 24 hours, if the level remains constant after the 24 hour sit, I'd work off that level.

I can understand how a hot fluid level is important to a shop, they don't have the luxury of allowing a vehicle to sit 24 hours so all the fluid could return to the pan and then check the level.

I'd be interested in knowing how this works out for you, report back if you can!

Thanks

 

[The_Eric]

Assuming the initial fill is correct, then yes, it'd be good to check it like that for reference.

 

[demarpaint]

Originally Posted By: The_Eric
Assuming the initial fill is correct, then yes, it'd be good to check it like that for reference.


That's the answer I was looking for. Now I'll pay someone to check the factory level before I do anything.

Thanks!

 

[lipadj46]

My Land Rover Discovery does not have an ATF dipstick. You drain it then refill it (underneath the truck with a pump) then start the car run through the gears then leave it in neutral and top it off while the truck is in neutral and still running. Nothing like being under a truck, with it running and in neutral. At least if the truck got away it is high enough that it can run over top of me without killing me.

 

[SteveSRT8]

The procedures vary wildly by manufacturer.

Not something you would want to mess up.

To correctly service mine you need an infra red thermometer and a dipstick calibrated in millimeters. You MUST have an accurate temp to get the correct fill level.

Again, it's not hard, just a few tricks you need to know.

 

[demarpaint]

The point I'm trying to make or uncover is this. If a vehicle is driven, then sits for 24 hours on level ground, and was filled correctly from the beginning the level should be the same 24 hours later, if it wasn't started or moved during that time. Now if it is driven and shut down and not moved for another 24 hours the cold level would be the same as before.

I can see where you need an infra red thermometer and a dipstick calibrated in millimeters, if you are attempting to check the level after a vehicle has been driven. Talking about millimeters I don't think most techs would bother measuring mm anyway.

I'm just trying to wrap my head around this. Once the fluid settles back into the pan the cold level should be the same? Hot level will vary with temperature.

I could also be way off base here, but anytime I checked any other vehicle that sat even over night the cold level was always the same on the stick.

I believe the hot level is needed for shops, service centers, or people on a trip that need to check fluid hot because they can't wait overnight or 24 hours for the fluid to drain back into the pan. JMO


I'm looking for a work around for the DIY guys that would rather not go to a shop or dealer.