1991-1995 Q45a Active Suspension reservoir capacity

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Infinitiguy19
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1994 Infiniti Q45a 240000 Miles

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The service manual says the Active Suspension system on a 1991 Q45 holds 6 Quarts (US). Surely all five quarts can't be in the reservoir so how much does the reservoir really hold?

Since Keith is still on here I hope you or 3Q Jay or Lino can chime in.
Last edited by Infinitiguy19 on Fri Sep 16, 2011 9:43 pm, edited 1 time in total.


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BCC93QT
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your q doesn't have active

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Infinitiguy19
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Never said I was going to put Active Suspension fluid in it....

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Lokim
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Infinitiguy19 wrote:The service manual says the Active Suspension system on a 1991 Q45 holds 5 Quarts (US). Surely all five quarts can't be in the reservoir so how much does the reservoir really hold?

Since Keith is still on here I hope you or 3Q Jay or Lino can chime in.

Probably less than a quart, and don't call me Shirley... :gapteeth:

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Infinitiguy19
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I just got the answer being 4 liters which is 4.22675284 US quarts (No disrespect to the previous posters). Next question is if it can stand up to the pressure of 35 PSI (MAX).
Last edited by Infinitiguy19 on Sat Sep 17, 2011 7:06 pm, edited 1 time in total.

texasoil
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Active reservoir will hold 3+qts.
Note--there ARE alternatives to Nissan Active Suspension Oil. Mercedes ZH-M mineral oil based hydraulic suspension fluid is a good one. AMSOIL 'Shocktherapy' 5 is a great one. these both cost about $10/qt.

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Infinitiguy19
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Alright basically what I am asking is can the Active Suspension (Act Sus) reservoir be used to hold Automatic Transmission (A/T) fluid? (For those of you that haven't got the hint already).

The problem I see is the cap in the reservoir blowing off from too much pressure. As we all (Should) know the Q45 A/T (Possibly all A/T's?) don't suck fluid in. Rather the pulling pressure of the pump is what keeps the fluid circulating.

I do wonder how this would affect the A/T fluid back pressure?

Would testing the container with air be the same as with testing it with 176*F Automatic Transmission Fluid (ATF)?

Now the great part of the reservoir is that its located just above where the Active Suspension cooler sits. So running lines shouldn't be any harder than the actual relocation of the cooler (If installed in front of the radiator/condenser.) And the great part is that the Act Sus reservoir has a level sensor and a temperature sensor. But one needs to make a harness and use the Act Sus Control Unit (CU) in order to view the data on a laptop or a Nissan Consult.

But I have a idea that might not require the Act Sus CU or much of a wiring harness. But it won't use the Nissan Consult or laptop interface either.

So are 3-4 Quarts/A/T Temperature sensor (Before or after the cooler, Depending on how the lines are routed) worth it? This all depends upon wheather the cap can handle up to say 40 PSI max pressure. I do suppose one could copy the Act Sus reservoir design and make a stronger one. Because after all who would want to replace a 4K A/T because of a a modification that was supposed to extend the life?!?! And of course clean a engine bad. :chuckle:

Q45JDM
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Hey all,

I'm new here, just got a Q45a and still trying to sort out the suspension issues.
My Actsus fluid is running low and it is very difficult to source it so I was wondering, could I top it up with something else from the ones you recommended (Eg: Amsoil Shocktherapy 5 or MB ZH-M) or do I have to drain the old Fluid A and use the alternative without mixing the two?

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Infinitiguy19
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You can't get the OEM stuff from the dealer? I have heard years ago you couldn't I was hoping that has changed.

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BCC93QT
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I recall a former member (Lino) adding about 1 liter of the Mercedes fluid to his existing fluid and no issues arose. On the other hand, he is no longer around...

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Q45JDM wrote:Hey all,

I'm new here, just got a Q45a and still trying to sort out the suspension issues.
My Actsus fluid is running low and it is very difficult to source it so I was wondering, could I top it up with something else from the ones you recommended (Eg: Amsoil Shocktherapy 5 or MB ZH-M) or do I have to drain the old Fluid A and use the alternative without mixing the two?
Last I checked you could still order the E2901-62u01 "fruid" (no joke). from the dealer. But don't expect any dealer, not even IoS to have it in stock.

I have mixed in 20% amsoil shock therapy lite on Keith's reco. Works fine. I have also put in about 4oz of lubeguard red.

Can't comment on other fluids.

Q45JDM
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Thank you all, I found the mercedes zhm alternative and will be delivered tomorrow! I'll let you know if I have any problems


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