Any tests to determine if my MP7 transmission is slipping or not ?

[fdryer]

Originally Posted by Silverblu02SL2

Looked up the spec: 59 hp, 81 ft lb torque!

Weight?

To make comparisons even when one is manual and the other auto, some base specs may need to be listed. Final gear ratio is also an unknown unless someone has specs.

'02 SL2; 124 hp @ 5600 rpm, 122 ft-lbs. @ 4800 rpm, 2,403 to 2,431 lbs

While not viewed at the right angle, is it possible the red xmission filter with a hard rubber gasket prevented from seating with the magnet? Would it seat better without the magnet?

[Silverblu02SL2]

Curb weight is around 2250 lbs plus about 150 lbs of stuff in the trunk. The Saturn was empty other than a gallon of washer fluid and 1/2 gallon of engine fluids and jumper cables. So both cars are around the same weight.

I didn't take measurements of either filter for clearance of the magnet. If they have the same clearance, wouldn't a hard rubber compress less and have more clearance of the magnet?

[fdryer]

Off hand and based on snapshots, I'm just wondering out loud (figuratively) about the clearance between the start of the threaded center portion of the filter cartridge and the outside lip perimeter along with gasket height above the lip. I'm imagining several dimensions to account for clearance to allow tightening canisters too allow gasket sealing as its crushed, tightening while having clearance between the filter lip and engine block as well as clearance between the top portion of female threaded filter center and male threaded section on the engine block. Perhaps somewhere among those dimensions, one is off preventing tightening the filter, bottoming, and preventing gasket sealing. This may be as simple as the wrong gasket material, perhaps too hard and not providing the seal needed as the softer one seemed to do the job. Bottoming oil or xmission filters isn't important as much as the gasket seal is crucial against oil pressure trying to force it's way out the weakest seal.

[Silverblu02SL2]

Just took a test drive. No more slipping when I floor the throttle! The car actually accelerates instead of doing almost nothing. So the leaky Carquest/ Advanceautoparts filter caused pressure drop to the valve body, causing the slip?

[OldNuc]

More likely low fluid level.

[Silverblu02SL2]

Originally Posted by OldNuc

More likely low fluid level.

I added less than 1 quart.

[fdryer]

Just took a test drive. No more slipping when I floor the throttle! The car actually accelerates instead of doing almost nothing. So the leaky Carquest/ Advanceautoparts filter caused pressure drop to the valve body, causing the slip?

I waited for this reply as I was on the fence about whether or not a leaking oil filter would affect xmission shifts. Apparently it does. I can't find any info describing the xmission oil pickup feeding the filter, if its under high pressure or not. Either oil is sucked into the filter before pressure is built or after pressure is generated. My guess is to suck oil before the pump to avoid high pressure ruptures or leaks as you found. If suctioning oil then air may be drawn in to create air/oil mix and throw off all shifts. Speculating without more info where the xmission oil filter is in the hydraulic circuit.

[OldNuc]

Look in the manual and you can see were the filter is fed from. It should take more than a little leak to drop pressure sufficiently to prevent lockup.

[Silverblu02SL2]

Drove the SL2 again today and no more symptoms of tranny slip. Could being down 1 quart cause the slip, or was it due to the leaking filter? Anyone with a diagram of the ATF flow path? Just curios. I hope to see improvement in mpg also.

[OldNuc]

Both combined are likely cause. The leak was larger than you think as that filter sees full line pressure.

[Silverblu02SL2]

I find it very difficult to read the level on the dipstick since it is light gray and smooth. Fresh ATF fluid is very pale and do not have much contrast against the smooth stick. When I pull it out, there is not a clear line where the level is, every part of the stick near where the level should be is wet! Very frustrating.

I think I am going take a hammer and a sharp punch and make around 50 shallow dimples on the stick to hold fluid. I think that will make it easier to read. Or maybe gun black it for better contrast? Anyone know how that's done? Is it some kind of acid etch process? I think soaking in vinegar overnight will turn it black.

[billr]

Naval Jelly (phosphoric acid) will turn steel a dull black. I think the resultant coating is iron-phosphate and even acts as somewhat of a rust inhibitor.

Yeah, I share your frustration of trying to read long trans dipsticks, and some are far worse that the Saturn.

[OldNuc]

Some naval jelly is a hydrochloric acid compound.

That is a spring steel blade and punch marks are stress risers.