external transmission filter - vital question!

[landtodd]

The external transmission filter may have been installed incorrectly (under recall) on my '92 Q45.

Dennis mentioned a couple of weeks ago that the external transmission filter was installed so that it didn't get the full flow of the transmission fluid flowing forward for cooling. That suggests that the filter was supposed to be plumbed in parallel with the in-radiator heat-exchanger -- a surprise to me!

You've guessed by now that my external filter was installed in series with the in-radiator heat-exchanger. So, when I bypassed the heat-exchanger with a transmission cooler, I installed it in series, just like the part I was bypassing. I didn't have any reason to think there was anything wrong with that until Dennis' comment.

Now, the question, which I'm really hoping someone can field -- will the external transmission filter flow enough to handle the whole cooling stream (seems possible, since the recall work was done years ago) or is the filter likely to choke the vital cooling function, reducing it to a trickle?

I must consider that this filter has 100,000 miles of transmission dust in it, so it won't flow "as new," and a new one is $145. Anyone know of a full-flow solution that would hold up under transmission temps? I was thinking about big canister-style fuel filters, but they're not likely designed for 200 degrees F.

Love the car, want the transmission to hang around as long as possible. The car will be on "light duty" until this is resolved one way or the other.

[Q45tech]

Oil filter or transmission filter are the same thing as far a the internal element is concerned.

The transmission flows about 4 quarts per minute at idle and maybe double that at high speed at anywhere between 20 and 30 psi.

So pressure is not a factor unless the filter is clogged just like when the in radiator heat exchanger gets clogged.

Why not replace it with a remote oil filter or anything BIG that will fit in the hoses.

Kind of foolish to not change a filter after every 15- 30k flush! But again they just wanted things to last 100k.

[landtodd]

Thanks for the reply, Dennis. I take your response to mean that the external filter -can- handle the full-flow, correct?

I will either pop for a new one (unlikely given the price) or mount an oil-filter relocation kit in its place. Excellent suggestion.

What's the number to make a transmission-service appointment at T-3? What's the best day of the week for that? Directions approaching from the South on I-95?

Thanks again!

[elwesso]

Sorry to bring back an old thread....... but on the 94s the external filter is right behid the radiator on the left?? What p/n of any oil filter does it use??? When i get the transmission flushed and pan drop/filter replacement, i might as well do this too!!

[Q45tech]

We have never changed the external transmission filter as it is difficult to get the part [no one wants to pay]....just getting them to flush is a major activity.If you purchase one from Scottsdale and bring it we will change.Don't assume we always carry transmission filters in stock as the demand for changes is low.

The thread was about getting a remote oil filter kit and plumbing it in to replace the sealed unit Infiniti used, so you could change the filter.

The point is when you make appointments be very clear with service writers what you want and remind them to order parts.

You would be surprised at what is not in stock at the 3 dealers we get parts from for Infiniti...........obviously they don't do specialized operations either.

[elwesso]

Oh..... so you cant change the black looking thing behind the radiator......

[Dinkydow]

Yes elwesso, you can change it. I just had mine changed along with a transmission pan drop, new internal filter and flush. I bought mine through Scottsdale. I don't have the receipt in front of me but I think it was around $50. Good Luck, I see your comments on the Caddy side to. Wayne

[elwesso]

Did you join cadillac forums yet...... if not, I suggest you do.....Its a great community, and I think someday it will be of NICO quality!

[Dinkydow]

Yes, I joined. I think it is a good site. I find it interesting that it is a different car but about the same type of communication, as far as little quirks the caddy has, as do our Q45's. I go by Big T over there. Talk at you later. Wayne