Is the only way to check trans fluid levels to overflow fill port?

[DreamSign]

Hello all,

I'm new here. Just got a 1998 Boxster base model with tiptronic that is slipping a bit.

Is the only way to check the ATF level to level the car, get the trans to operating temp and fill the fill port until it overflows?

Thank you in advance for helping a newby.

[DreamSign]

My question is if there is a trans dipstick hidden somewhere?

[A8ked]

There is no dipstick.

[DreamSign]

Thank you for the fast reply.

I drove the car a bit to get the trans up to temp, lifted it level, and added a full quart of the blue bottle Trans-x. About 1/2 quart went in before anything overflowed, I suspect that means that the trans was approx 1/2 quart low.

There is some leakage on the outside of the trans, I didn't get a good look as to where it is leaking from. I sprayed some good PB 80 penetrating oil on the pan bolts, so in a week or so when my filter and gasket arrive from Pelican, hopefully all bolts cooperate and come off easy.

My plan now is to drive it easy a bit, 100 miles or so, then drain and fill once about 3.5 -4 quarts seems to be the general belief of what comes out when you remove the drain plug. Then, after the filter kit arrives, I'll remove the pan, change the filter and add another bottle of trans-x blue bottle and fill the rest with new OEM ATF 1 fluid.

Does everyone agree with this, or if not, have suggestions and reasoning why some other course of action would be better?

The fluid is black and done, I'll see if the first 3-4 quart drain and fill improves or degrades the behavior of the trans shifting and report back here.

[A8ked]

Getting to the Transmission Sump Pan is a pain (lots of things to remove first), but it is straight forward and replacing the filter is easy.
Refilling the Transmission fluid is a bit more complicated, but not difficult. You will find a laser thermometer helpful to determine the fluid temperature when you are refilling.
I used the VERY EXPENSIVE Porsche recommended fluid and as I recall needed about 4 Qts.
The most difficult part was reinstalling the aluminum Transmission Pan cover under the Transmission.
I found the 101 Projects book instructions to be very helpful.

[DreamSign]

The video I found on youtube really helps. I don't anticipate any issues doing the trans service (as long as no bolts snap) I have already sprayed the bolts with a good penetrating oil.
I jacked the car up today level after getting it up to temp, did a drain and fill, but only 2 1/2 liters came out, so I only changed 2.5 liters. I'll drive it a bit, and do this again a few more times it looks like. I expect my filter and gaskets to arrive in a week or so. Maybe I can get closer to 4 liters out when I remove the pan...

The car originally was .5 liters low and the trans slipped a bit. Now filled up it is behaving much better. Smooth 1-2-3 shifts. 3-4-5 there is still a tiny rise in RPM between shifts, but much better than before. Changing just the 2.5 liters, shifts feel a bit better too, not worse, so that gives me hope when I change more fluid it won't slip, but I'll only know after I've done the service.

[Stl-986]

You will end up regretting the fluid you put in...and how you did it. Might as well start to save for a rebuild at some point.

The filling process is very specific, do a search and you will find it, but from what you describe....you mixed fluids & didn't fill it properly.

[DreamSign]

Originally Posted by Stl-986

You will end up regretting the fluid you put in...and how you did it. Might as well start to save for a rebuild at some point.

The filling process is very specific, do a search and you will find it, but from what you describe....you mixed fluids & didn't fill it properly.

So you are saying this video is giving incorrect information?:
https://www.youtube.com/watch?v=F8wSAPF582g&t=181s

I used that exact fluid.

[Starter986]

Originally Posted by Stl-986

You will end up regretting the fluid you put in...and how you did it. Might as well start to save for a rebuild at some point.

The filling process is very specific, do a search and you will find it, but from what you describe....you mixed fluids & didn't fill it properly.

Not knowing when last my 98 had an AT service, and I was at around 115K miles, I decided to drain and refill... changing out the filter as well. My research revealed very specific instructions incluidng car level... laser thermometer... everything down to a T.

I purchased the OEM filter and most specifically... The Pentosin 1. I did copious research on alternative, and less costly, fluid... but was reminded and encouraged to go Pentosin.

The car had NOT been acting up... but I wanted a benchmark moving forward.

Before embarking on the task I was 'warned' that shortly thereafter the transmision could fail.










Shortly thereafter... within a couple tousand miles... the transmission main seal failed.

$4,300.

OP... be certain to keep us posted, and don't go ghosting us when you hit the side of the road.

Me, based upon the comments you've inspired, would be taking the car to a shop and having the transmission properly serviced. Good luck.

[DreamSign]

I can easily promise that I will report back honestly whatever ends up happening.

So far I have only changed approx 2.5 liters of Pentosin ATF 1 and I've added 1 bottle of the blue trans-x. The shifting is much improved. Much improved. I still get the occasional hard shift, but I've only driven it 70 miles since adding the trans-x.

Since the fluid has likely never been changed with 113K on the odometer, and the fluid is black and no longer able to function as it is supposed to, I am going to do the filter service and change another 4 liters of fluid.

My parts just arrived from Pelican and I plan on using my buddies lift to help do the trans service middle-end of this week. I will report back if it is better or destroyed.

I test drove a 2006 and a 2016 Boxster yesterday. I still prefer the smaller feeling 986, though I might sell this one after fixing it up a bit and swap for another 986 "S" with a manual trans since I prefer manual in my sports cars.

[JFP in PA]

The fluid in the Tip should not be allowed to run more than 50K miles without service, sooner if you are capable.

In your situation, you are going to need to fill, run up to temperature, then dump the fluid at least three, preferably four times before you get most of the crud out of the trans. And I would leave the original filter in the trans until after the third dump, then install the new filter.

Running any gearbox 100K miles between service is just plain nuts...................

[DreamSign]

Originally Posted by JFP in PA

The fluid in the Tip should not be allowed to run more than 50K miles without service, sooner if you are capable.

In your situation, you are going to need to fill, run up to temperature, then dump the fluid at least three, preferably four times before you get most of the crud out of the trans. And I would leave the original filter in the trans until after the third dump, then install the new filter.

Running any gearbox 100K miles between service is just plain nuts...................

Yes, I will take this advice. I bought extra fluid, I bought a total of 13 liters. My plan is then to drive it to the lift, drain and fill, drive it around the block in all gears, drain and fill, repeat until I have only 5 liters left of fluid, then do the service of changing the filter and removing the pan.

As a reference I believe in preventative maintenance. I have four X308 Jaguars with automatic trans, and I have done preventative trans services on all of them, despite the loud voices on the Jag forum saying if it isn't broke, don't fix it. The way I see it, trans fluid has a limited life, so running it until there is a problem significantly increases the chances of there being a problem...

[DreamSign]

Trans service done :0)
Used my buddies lift, much easier than in my driveway.
Car shifts better :0)

Did a drain and fill, drove around the block, then drain and fill, drove around the block
Then pulled the pan, no metal of any kind on the magnets- yay!
Swapped in new OEM filter (pelican)new drain and fill plugs, oem gasket
Added 1/2 blue bottle of Trans-x and the rest the ATF fluid that was on sale at jiffy mart...
..Just kidding, used the ATF-1 as required. Trans was at temp to top off, took more extra than I was expecting. Now it drives fine.

[DreamSign]

New filter from pelican