1998 Infiniti QX4 4WD transmission fluid advice

[EliteScouter]

Hey everyone,

I just picked up a 1998 Infiniti XQ4 4WD with 164k miles and I want to change out the transmission fluid since I have zero info on what and when anything has been done on this car. I just know that water pump was replaced less then 5k miles ago and that's it.

The fluid doesn't look too bad and the transmission shifts super smooth, I want to change the fluid out and I know it can be done with dropping the pan to clean the magnet and replace the mesh filter. This method does not get all the fluid and I am not sure if the transmission will be ok with mixing fluid since I don't know what the previous owner put into the transmission. I read that it can also be done with transmission cooler drain and fill to get the 10-11 Qt's.

Anyways I would just like some advice, this is a gem very well taken care of outside/inside and runs smooth. I just want to make it ready for our family by doing fluid changes/sparkplugs/coolant flush/ and etc.

I would just like to know what method would you guys prefer and what fluid should I put in it. I am assuming the transmission is original with the 163k miles.

Thanks!

[Blindaviator]

Since these trucks don't have a real transmission filter it is usually just as good to do a simple drain and refill... You can do the cooler refill or you can do a drain & refill multiple times over a few day which will get most of the old fluid out...
I picked mine up with a little over 200k miles on it and the trans still shifts fine...

The "filter" inside is nothing but a gravel catcher... What many do is add on an inline filter on the cooler lines such as the Magnefine which has a magnet built into them...
http://magnefinefilters.com/

[EliteScouter]

Ok I did the change and everything is smooth and all. However, the thing that bothered me before flushing is still there. Not sure if it's normal but going from 1st to 2nd the RPM's drop slower than when it goes from 2nd to 3rd and so on. Here is a video I recorded, you will hear engine and the RPM's falling slowly when shifting from 1st to 2nd.

VIDEO: https://youtu.be/H_LoROg_pKc

Not sure if this is normal or if I need to replace something but it's just bugging me. It drives fine, no hard shifts or clunks.

[Blindaviator]

Ok I did the change and everything is smooth and all. However, the thing that bothered me before flushing is still there. Not sure if it's normal but going from 1st to 2nd the RPM's drop slower than when it goes from 2nd to 3rd and so on. Here is a video I recorded, you will hear engine and the RPM's falling slowly when shifting from 1st to 2nd.

VIDEO: https://youtu.be/H_LoROg_pKc

Not sure if this is normal or if I need to replace something but it's just bugging me. It drives fine, no hard shifts or clunks.

It could be a learned behavior from the previous owner causing it. You could try resetting the ECM and have it relearn your driving habits and see if that helps...

[EliteScouter]

I left the negative battery unplugged for 6 hours. That reset everything.

Changed out the motor oil, front/rear diff fluid, and transfer case fluid. Cleaned the MAF sensor, changed the oil and air filters.

Runs really smooth, just the slow RPM drop during shifts kinda worries me that the transmission might go out.

I never owned a new one of these so I don't know if that's normal.

[Blindaviator]

Slow shifting almost sounds like a servo possibly getting worn out... Hopefully someone with more knowledge of auto transmissions will chime in...

I know quite a bit about most parts of a car but the auto trans is one of the few I haven't had to deal with too much... Usually if I start having issues with a transmission and believe it needs a rebuild I will look into getting one through Vatozone... The price there is about on par (sometimes a little higher) with most transmission shops and they give a LOT better warranty... You can get one from Vatozone for about $2000 with a 3 year unlimited mileage warranty... Most transmission shops will charge 1500+ to rebuild one and usually only give a 90 day warranty not to mention you are limited to that one business for warranties... If you end up having to move to a different city or state your warranty is pretty much gone...

[EliteScouter]

Oh, if it went out I would just simply change it out with a low mile JDM transmission from ebay for $500. The car is not worth more than 2k, so no point in putting that much into a car that gets driven maybe 3-5 times a month, short distances.

[Blindaviator]

Oh, if it went out I would just simply change it out with a low mile JDM transmission from ebay for $500. The car is not worth more than 2k, so no point in putting that much into a car that gets driven maybe 3-5 times a month, short distances.

Yeah that would make more sense for the amount of miles driven... If you drove like I do then the $2k would be for me...

[MisterH]

Ok I did the change and everything is smooth and all. However, the thing that bothered me before flushing is still there. Not sure if it's normal but going from 1st to 2nd the RPM's drop slower than when it goes from 2nd to 3rd and so on. Here is a video I recorded, you will hear engine and the RPM's falling slowly when shifting from 1st to 2nd.

VIDEO: https://youtu.be/H_LoROg_pKc

Not sure if this is normal or if I need to replace something but it's just bugging me. It drives fine, no hard shifts or clunks.

It could be that a shift solenoid is sluggish, but there are some much less expensive repair options for you than replacing it with another used transmission. You can purchase all three new solenoids for less than $75 and install them yourself in 2-3 hours from start to finish. If you want to take it a step further you can purchase a new complete valve body assembly (solenoid pack already installed) for about $350. It's a little trickier, time consuming job to tackle at home simply because of the awkward position of doing it while laying on your back under the vehicle. However, a skilled transmission repair guy can do it in about two hours if you need to take it to a professional. As long as your internal clutches are not burned up this would be a much safer, more cost-effective gamble than doing a transmission swap with another used unit.