Does tranny fluid WEAR OUT??
- Thread starter wcbcruzer
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Yes, the fluids shears out of viscosity. the fluid has very little additives so these also get depleted over time.
Yes it will wear out. I recommend a remote oil filter mount plumbed into the cooler line. Not a big fan of bypass system on the trans. I use a WIX 1269 ( not sure if got the number right, just to lazy to go in the garage and look.)
Using Mobil 1 oil filters on the car's trans right now. Got them real cheap on e-bay so I couldn't pass it up.
Another alternative is the wix 1040 ( Once again not sure if thats right but to lazy to go to garage and look)
Using Mobil 1 oil filters on the car's trans right now. Got them real cheap on e-bay so I couldn't pass it up.
Another alternative is the wix 1040 ( Once again not sure if thats right but to lazy to go to garage and look)
If you are going to "tee" off of the output line and "tee" back into the return, I think you would be okay. You would have transmission cooling problems if you were to try to simply put it in-line on either the output line or the return line due to the restriction required for proper bypass efficiency.
BTW, why does ATF shear and how can it be prevented -- syn is one option but then if a tranny (JATCO) is predisposed to chew up the fluid what can one do.?
I don't see my engine oil shear that much based on my UOA.
I don't see my engine oil shear that much based on my UOA.
Not sure of your application. The bypass system won't hurt anything if plumbed in correctly. Plus, some filtration is better then no filtration. My suggestion is a cheaper alternative. Regardless of what system you use your fluid will still get dirty and oxidize. So, it would still be wise to change the fluid. However, if you do not like changing trans fuid then running the filter will extend the life of it to an extent......
I've seen many trans go a long, long, long time with no maintenance at all.
I've seen many trans go a long, long, long time with no maintenance at all.
A higher quality, say synthetic or syn blend ATF will not shear or wear out nearly as fast as a lower quality regular ATF. Equally important is keeping the fluid at a reasonable operating temp to protect the fluid from chemically degrading (oxidizing and overheating). This can be accomplished by making sure your cooling system is operating properly, or better by adding an additional cooler in warm climates or other hot operating conditions. Cooler fluid means a cooler trans, with seals and other soft parts that will hold up muchlonger. Lastly, to make ATF last longer in service, you will need to add additional filtration to the cooler line circuit. This is one thing Honda did with their somewhat unreliable FWD transaxles, to help remove some of the wear particles that were causing reliability problems in these units. The normal ATF filter found in the sump/pan of most trannys is on the suction side of the pump and cannot filter well enough to keep the fluid truly clean. A filter somewhere on the pressure side of the pump, such as in the cooler line exiting the trans, is a much better way to keep the fluid useable and from being "worn out" so quickly.
Thanks for the info guys. I've got a Dodge Ram Cummins with the 47RE automatic trans. I agree that the sump filter isn't very efficient. The problem is, the darn tranny hold 21 quarts of fluid.
On a regular drain and refill, it takes almost 10 quarts. Since I haven't changed it since I bought it, and I don't want to have it flushed, it'll take a few drain and refills to get the fluid nice and clean. That could do some damage to my wallet... I was hoping that I could add the bypass filter on the next drain and refill (which gets rid of about half the tranny fluid) and not have to worry about it for a while.
However, I'm beginning to think maybe I should just do a couple drain and refills and call it good. I finally convinced myself it was ok, but deep down I don't really like messing with the tranny because it's a sensitive thing that costs major $$$.
However, I'm beginning to think maybe I should just do a couple drain and refills and call it good. I finally convinced myself it was ok, but deep down I don't really like messing with the tranny because it's a sensitive thing that costs major $$$.
I'd forgo the additional tranny filter, and invest the time/money into another fluid change.
A filter won't cure the basic problem of worn out fluid.
If you NEED an filter for particulate matter, you have a trans with problems.
A filter won't cure the basic problem of worn out fluid.
If you NEED an filter for particulate matter, you have a trans with problems.
Look into a remote oil filter mount. Look at permacool website, this will give you some basic information. There are other choices. You get the best of both worlds. Better filtration then stock that won't cost as much as bypass. Look at Wix website and look up napa gold #1269 and wix #51410. These are what I run on my trannies.
Yes the transmission fluid will 'wear out'. Just exactly how it will wear out and how fast obviously depends upon how the fluid is formulated and what sort of duty cycle it is subjected to.
Fluid can be degraded through thermal stress and that can be just plain old oxidation of the base oil. This was probably the most common degredation back in the days when most ATFs were based on group one basestocks. That's how PAO based fluids obtained their reputation, they are much more thermally stable than group one based formulations.
However, since most fluids have now moved to group 2, 2+ and group 3 that picture has changed. These days a well formulated fluid will not 'break' due to thermal degredation of the base oil as the first cause. In fact a well formulated group 3 fluid will out-perform a POA based fluid 9 times out of 10.
The weak link now is the shear stability, which is overcome in most modern fluids by improved VMs, and thermal stress of the additive package resulting in changes to the friction characteristic that may give rise to problems such as TCC shudder.
Of course, there are other factors that will cause the fluid to degrade over time, such as wear metals, water contamination etc that can cause the additive package to 'fall apart' and /or adversely affect antifoam and aeration qualities.
Hope that helps a little.
Fluid can be degraded through thermal stress and that can be just plain old oxidation of the base oil. This was probably the most common degredation back in the days when most ATFs were based on group one basestocks. That's how PAO based fluids obtained their reputation, they are much more thermally stable than group one based formulations.
However, since most fluids have now moved to group 2, 2+ and group 3 that picture has changed. These days a well formulated fluid will not 'break' due to thermal degredation of the base oil as the first cause. In fact a well formulated group 3 fluid will out-perform a POA based fluid 9 times out of 10.
The weak link now is the shear stability, which is overcome in most modern fluids by improved VMs, and thermal stress of the additive package resulting in changes to the friction characteristic that may give rise to problems such as TCC shudder.
Of course, there are other factors that will cause the fluid to degrade over time, such as wear metals, water contamination etc that can cause the additive package to 'fall apart' and /or adversely affect antifoam and aeration qualities.
Hope that helps a little.
My understanding it's the coefficient of friction that is important in atf's. If the fluid falls out of the range that the transmission should have for proper operation, things may not work right or slippage could start. This is regardless of how filtered or cooled the fluid is. Since I have no good way to test friction coeffcient, my only best bet is to start over with new fluid at reasonable intervals.
Yes, these days the primary concern is changes in coefficient of friction. However, most modern fluids are quite durable in that respect, as long as they're not contaminated. So if you follow the manufacturer's recommendations, generally you should be OK. The danger with added filtration is that if the pore size of the filter is too small, it will actually damage the fluid in itself. The particle size of ATF antifoam is in the region (and there is obviously variation) of around 6-10 microns so a 2-micron filter could damage the antifoam performance of the fluid.
I can tell you for a fact and with many UOAS Mobil 1 ATF shears down as quickly as non Syn ATF.
Good info to know. I would have never guessed it would actually be bad to filter out particles that are in the 2 micron range. I'm not going to be putting a filter on the trans after all. I'll just stick with the regular drain and refill until it's clean. I just installed a drain plug in the pan so it should be a lot easier now.
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