Fluid Changes

[911/Q45]

What's the best way to drain the old fluid out of the power steering on a 1990 standard Q? When I change the trans fluid I'm dropping the pan and changing the filter. How much fluid will be left in the trans if I let it drip overnight? I have a Griots Garage oil siphon that sucks fluid out through the dipstick port. Would it be worthwhile to run the car around a bit, then suck out a few quarts and refill with fresh after the filter change and pan cleaning?

[DAEDALUS]

This was discussed recently on the old board, but I can't seem to find the article now. Put down some plastic, cause it is a really messy job. The manual states a 90 Q holds 9 1/8 quarts. If you let it sit, you should be able go get about 7 quarts out (just over 2 qts left in the transmission). One trick is to periodically shift from gear to gear (car off, of course) using the shift lock override button...this will free up a little more fluid. I've made a point that if you get 7 qts out, you can drain the transmission fluid 2x and have 95% clean fluid--better than a single machine flush and for less money. The more you remove, the better. E.g., if you get 8 qts out each time, you will have 98.4% clean fluid when done, though you'll then need 16 qts total instead of 14. Of course, if you can get 8 1/2 qts out in one try with the siphon, that would get you to 93% for pretty cheap with less labor. Don't forget to inspect and clean the magnets on both the transmission pan and the differential plug to get an idea of how healthy the internals are. You will probably want to put some kind of cleaner in the transmission fluid before flushing. Anyone care to recommend a product?

[911/Q45]

I did this on my first Q and it was very messy. I'm hoping for a neater job this time because I can suck the pan dry, let it sit overnight and suck it dry again before I open it up and change the filter. I'm not looking forward to what I find on the magnets, but my last Q was pretty scummy at 60K and yet it's still running the same trans at 130K+ even after overheating a few times with a bad thermostat and no trans cooler. I told the second owners that they should replace the guides, but they're not interested. Any ideas on the power steering fluid?

[landtodd]

Last time this was discussed, Dennis and others used Mobil 1 synthetic ATF for power steering fluid. I changed last month.

Change method: Extract as much as possible from the PS reservoir with a turkey baster, refill with fresh, drive some, do it again. I've refilled the reservoir six times, used a quart of ATF in the process, and the fluid color has gone from dark, dark brown to pink-tan. I'll probably go though another quart before I'm satisfied.

After the first time, you get progressively faster and make less of a mess.

[maxnix]

Kirkland Infiniti has a power steering pump flush machine. I am getting the service soon, so I will try to verify what it is.

I will also check which transmission flush machine they have as they prefer it to the BG they had used previously.

They also use the Envirolution crankcase flush machine, with which I am impressed as being very effective, especially on the top end.

Remember, if your fluid doesn't appear as new, flush, flush again until it does. Every discoloration is contamination.

[Q45tech]

It amazes me how many racks we have to replace prior to 160,000 miles.....between not spending for leaky worn boots and failure to change power steering fluid......[thank you Lexus engineers for the 3 filter screens which clog and moan] we appreciate the business.Nissans are a little better but still by 200k or 150k [12] years.

The Q pumps are bullet proof but they wear and the pressure declines, normally there is enough extra so most don't notice except in radical manuvers.....the 90-92 with faster steering shows up first as the pinion wears and the rack doesn't dampen the tire/wheel vibration allowing you to feel it in steering wheel and on center play.

Great to use Mobil 1 SYN ATF as the temperature in summer gets excessive [not enough PS cooler just a single tube across rad].Measure the temp in the storage can -- 200-220F.

Original rack 236,000 miles [12.5 years] never a leak but 2nd set of boots and bushings plus new tie rod ends! In fact never replaced a hose [probably tommorow a leak]

[maxnix]

Had power steering flushed with mineral oil, then refilled with Mobil 1 ATF today. Writer thought it was a Snap-On system, but wasn't sure.

Fluid was darker red, but not blood red. It was worth doing it right with the right tools (~$90 with my fluids and their mineral oil) to get any heavy contaminants out. Dennis is correct when he says the fluid in the steering rack and pump is subject to high thermal loads with no cooling reserve. Mine was 7 years old with ~32K mi.

Writer did not know the name of the transmission flush machine, but did mention it does not rely on the transmission pump, and it circulates the fluids in the opposite direction from the BG machine. They are not hip to pan drops and filter screen replacements.

He did mention that Formula one had totally whacked a Q transmission with their flush machine. Injured party received check and took car to another facility for repair. Also bought another Infiniti that following weekend. Go figure.

Mentioned they had switched to an Envirolution cooling system flush machine.

I'll call the service manager and see if I can get the brand of the other two machines.

[Q45tech]

All the flush [should be called fluid exchange] machines depend on the [transmission or power steering or water pump ] to do the pushing/pulling work.The FLUSH part is the chemical solvents detergents which loosen the crud up that the standard fluid has allowed to collect.Wherever there is magnetic material [gears, etc] there is a magnet in each sump [diff, transmission, oil pan] to attract and hopefully hold this worn off material between manual cleanings.

Did a flush on a members car yesterday [190k 90 Q] second transmission [because it had a drain plug] so somewhere between 120k and 70k was my guess as to current age [blackish/brown ATF], rad had been replaced so the dealer probably did it from some of the signs [precision technican].

The pan magnet's entire surface was covered to 1/8" with magnetic material, the pan bottom/sides were intermediate with slime, the filter was orange/brown with resinous baked in residue. The initial pressure on recirculate was 13 psi [not 20] after the flush, new filter, and an external cooler install, the pressure [in the cooler lines] increased to the normal range ....the exchange took 4.2 minutes vs a more normal 3.5 so only 20% slower. The worst I have seen was 6.5 minutes

It is very important for whoever is doing the work to understand the full scope and norms so they can report to you.

Anyone you says they don't think pan drops/filter changes/magnet cleaning are necessary needs to have his credentials checked as they must have skipped transmissions 101 in trade school.

We also replaced the entire rack and bushing and both tie rod ends! The transmission mount, oil pressure sender, did an injector rail flush, removed massive amounts of dirt and leaves from the radiator and condenser space.

[Q45tech]

Shiny red vs blood red vs red!Simple place some new on a paper towel, clean the dip stick, place some old on the towel, place the new after flush ATF from the again cleaned dip stick compare the color if what you get is not identical the flush was not complete.Nothing wrong with doing it again immediately as the machine can be drained of the old and refilled in 10 minutes.

We offer a 20% discount on the second flush if required since the hoses are still attached and the car is already on the lift.

I would say that half the time the transmission could use another reflush but only 10% of the time do we force the issue, just tell the customer to come back in 6 months or a year for another one.

After all they didn't really understand why it needed one in the first place and they are not used to every 3 day dialyisis.I almost never get a new customer who asks for a flush you have to spend 10 minutes explaining how it will save them money. When you say 90-120 day engine oil changes they look at you funny.

If your blood looked like most of the fluids we see you would have been dead for 2 days!

[AZhitman]

Did a flush on a members car yesterday [190k 90 Q] second transmission [because it had a drain plug]

Dennis - Does this apply to a 95 model as well? I just did a series of 3 overnight "drain and fills", dropped/cleaned the pan and replaced the filter. Mine has a drain plug, but no evidence in the service Hx of a trans replacement.

[BradM]

Q45Tech said: "Anyone who says they don't think pan drops/filter changes/magnet cleaning are necessary needs to have his credentials checked as they must have skipped transmissions 101 in trade school."

A little off subject, but would this (filter chng) apply to ALL vehicles getting the BG transmission flush? I'm getting my Ford SUV ('97 Expedition)transmission flushed on Monday by dealer. Service writer says filter is just wire mesh screen and they don't recommend changing it. Should I insist on this for my SUV just like I would for the Q? Again, I apologize for it not being Q related, but hey we all have second (or third) cars right?

Thanks,

BradM1990 Q45, 205,000Sumnmer transmission change club

[DAEDALUS]

I think replacing the filter is a rule that is applied to all cars, but only if the filter does what it's supposed to do. Any filter that does its job gets more and more clogged as time goes on; the more clogged it gets, the more pressure drop the transmission system will see. This is never good for the car. Others have said it and I'll repeat it here--the service writer makes a bigger bonus by replacing your transmission than by replacing your filter. I'm not saying he or she is unethical. It could very well be that the official stance by the manufacturer is that the filters do not need to be replaced. Of course, the manufacturer too has a vested interest in selling you a new car every 5 years than having you drive around in a cherry 13-year-old car. Here is a pic of DougQ45's filter when he had it removed:

[Q45tech]

Wow that's a VERY VERY bad one! To me if its just discolored not shiny bright aluminum in the view port it's bad. Most we change are nowhere near this bad.

Each transmission is different and Ford is nowhere near the most reliable [Lexus then GM., JATCO........,ZF,,.....Ford......finally Chrysler at the very bottom. Almost every one makes a good transmission that last through the warranty.Ever see the automatics used in the big rigs, they are as big and strong as the Q engine and they hold 40 quarts of ATF vs 10 for Q or 14 for big MB.

Based on a frequency report from the American Transmission Rebuilers Association. Most say if it wasn't for Chrysler they would have had to layoff staff in the downturn.Unfortunately the report wasn't model specific as GM makes many transmission for BMW and JATCO makes many FWD for sale in Europe: Rover, Saab, etc.

The longest Q transmission we have seen is in a 94Q [2nd owner at 60k] with 255,000 miles, we have two early LS customers with over 310k obviously lots of highway means fewer shifts! They all get regular 30k flushes and have since they purchased cars new.

It sickens me to see a 133k 90Q all ragged out with a blown motor or transmission, but then again it made it 63,000 beyond the warranty.

[VimyJ]

Wow, that Q pan is way worse than mine was! I had mine changed (probably for the first time) at 70K. The metal was still shiny with less than 1mm of material around the magnet. The new replacement filter had been redesigned. (Perhaps an acknowledgement that the transmission was a little less robust than Nissan thought?) The pan drop is a messy time consuimg proceedure that may need to have repeat visits to correct any leaks from the reinstalled pan. It's no wonder dealers would rather have more lucrative repairs taking up space on the lifts.

[BradM]

Guys,

Thanks for the reply. Had heard the same thing regarding Chrysler transmissions. I'll see how much extra the dealer will charge otherwise I'll do it myself. Like any transmission filter change, it is a messy job so I don't mind paying the extra hour labor for them to get dirty. I'll re-fill with Mobil One ATF of course and add lubeguard.

My Q transmission lasted 204,000. Lots of Texas highway miles. Last 40k in Pittsburgh. It was original and from what I could tell did NOT have the dealer modification done (fins just fwd of transmission). Also, no drain plug. Not many fluid changes in its' life. I didn't do one in the last 45k.

Brad1990 Q45, 205,000

[maxnix]

911/Q45

I had my power steering fluid flushed and replaced at dealer using mineral oil for the flush, replaced by Mobil 1 ATF. I will determine equipment used when time permits. Old fluid was ruby red.

It seems to be flushing this component is preferable to mere siphoning as any metal bits from wear would not be removed with a baster. I think that t models require an extra quart of fluid as the PS pump drives the HICAS rear wheel steering.

[911/Q45]

I just changed trans and power steering fluids and had some interesting results. At 53K miles and almost 13 years the trans fluid was in pretty good shape with very little metal on the pan magnet. The power steering fluid was quite cooked, in far worse shape than the trans fluid. I siphoned out the trans, let it drip overnight, then siphoned again. No mess when I dropped the pan, but about a pint drained when I removed the filter. I figure I got all but about 2 quarts that were in the torque converter, so in 100 miles or so I'll siphon out 4 more quarts and replace with fresh. The power steering I drained by disconnecting a big banjo bolt between the pump and the rack. Estimate I got about 80%, so I'll do that again in 100 miles too. That Griot's Garage oil sucker is worth every penny of the $70 cost!

[maxnix]

Just did what Dennis suggested and checked old PS fluid against new fill against automatic transmission fluid. All resolved to pale pink on clean white towel.

Oil is very light brown with 3K miles on M1 10-30W.

[DougQ45]

My first post on the new website. Too much new stuff to learn!!Just some history after looking at the photo of that old transmission filter. Had just bought that car with 86,000 miles when the owner said the trans went out and it stopped running. He couldn't understand as it ran great until he took in to the dealer who just flushed the trany (and also ran a cleaner thru it). Got the car going shortly after having it trucked to my house but noticed a terrible transmission "whine" and slipping that Q45tech diagnosed as "drop pan... replace filter... clean pan". This I did and was shocked at the filth I saw. The picture was AFTER I scraped away a bunch of the filth to see what it consisted of. After looking at the car history, the first and ONLY transmission service was a flush at 85,000 miles. Obviously, it flushed all of the crud right into the pan where it got sucked into the filter. Oh yes, also clogged up the heat exchanger in the radiator which I finally got cleared when I put in the transmission cooler. Finally after 2 pan drops, 2 more filters and a final flush, I got everything clean. I called the dealer and asked them about replacing the filter for a trans service. They said they don't do it as a matter of policy, and when I told them my case story they did not take it well. The service adviser said the filter usually leaks after replacement which was the biggest load of H.S. one has ever heard. Alot has been written about proper service and this is a testatment. "Drop pan...replace filter...clean pan." The car now runs great. Nice to be back.

[PalmerWMD]

Doug , good to see you here !

Looks like we finally have almost all of the usual suspects back..

Except I am still waiting for Leadfoot to come on...Anybody got his email?

Fred...