I have an 05 G35 and her miles are getting on the higher side, currently at 125k and I have heard horror stories about the transmissions of these cars. I had a few questions.

How long on average do the Auto Transmissions last before they need rebuilds?

I highly doubt the car has ever had a transmission flush, would it be a good idea to perform one?

Is there anything I can do to extend the life of this transmission?

Will driving in manual mode reduce the life of this transmission?

If I ever have to replace or repair it, where should I go and how much does it cost?

 

Just pan drain and fill with the fluid recommended on the transmission fluid sticker under your in your bay. Flush can kill the engine.

Extend life? I don't know... Pan drains every 3rd oil change?

Manual mode... Let's just say yes because it makes you drive more aggressively.

Repairing wise any transmission specialty place will get the job done. It's NOT cheap.

Hope this helps.

 

No. 1 killer of ATs is heat. Do everything you can to reduce that - keep fluids in check, invest in a dedicated transmission cooler.

Do NOT flush your transmission. You run the risk of loosening seals and particles that are actually important to the transmission's integrity.

Upgrade your Valve Body - TransGo specifically. Model No. RE5R05A-HD2

Like I said, get a transmission fluid cooler. You can piece together one yourself, or go with any of B&M's coolers and grab an extra 4' of 3/8" coolant hose (kit only comes with 4'). You don't need to go huge with daily driving.

Definitely drain and fill your transmission fluid - just like a regular oil change. Drain from the bottom pan/plug, fill from the top with a funnel (8 quarts or so).

If you have never changed your fluid, check it now. If it's brown or smells burnt, scratch the drain and take it to a dealer to have to flushed and filled.

FYI - AT fluid should be changed every 30k miles.

 

Had you followed a strict maintenance schedule with your Infiniti you wouldn't have concerns now! Do a drain/fill now using only Nissan AT fluid, in 60 days have it done again and I'd do it one more time in November. That should allow the trans internals to get clean and work well. Don't worry about rebuilding your AT unless you ignore our suggestions.
Gary

 

Our drain and fills are 8 quarts...? Really?

 

It's been a while since I've been here! My suggestion would be a buy a highly reputable ATF or Nissan Matic J or whatever letter it's up to and do a full transmission oil and filter change. Whether you drop the pan, change the filter or not I'd advise to first check the level with the car running via the dipstick to make sure it's within normal range. Then measure the amount of oil that you drained from the pan. This way you don't overfill. Maybe this summer I'll do a full flush of the ATF (old '95 Maxima never been changed) and report back.

 

Use Nissan ATF or an equivalent. I went with Idemitsu type-J only because I got them dirt cheap about 5 dollars a bottle (normally 10-12). It's an OEM equivalent.

You can do the flush while the car is running if you're feeling bold. You basically unplug the outlet hose and put new fluid in while the car is running. Then monitor the output hose until it starts putting out new fluid.

Personally, I've always done the drain and refill. I've noticed how much comes out depends on how high you jack the car or if it's at an angle. I got ~6 quarts out one time when it was pretty high off the ground. You should get about ~4 quarts though if it's jacked just enough for you to get under and change it.

But, always buy a little extra then you need, since you don't want to be in a situation where you can't replace what you took out.

 

I checked my transmission fluid the other day and it's definitely burnt. Above it says if it's burnt do a flush but ive heard that you shouldn't flush these transmissions. Do I flush or just a couple drain and fills?

 

Do 2-3 drain and fills with a couple of hundred miles in between and you should be good to go.

 

Where do you get Idemitsu Matic J for $5qt? I remember google searching for it and it not being cheap. I have Castrol ATF waiting. That was about $7qt.

 

Smyth auto sells ATF that replaces J Matic for $5 a quart.

Is it wise to jack the rear of the car higher to get more oil out and is it also smart to drop the pan. Tbh I don't know if the filter has ever been changed or if it is easy.

 

The flushes everyone is talking about is when they hook a device up to your car and pump fluid through it. The flush I was referring to uses the transmission itself to push the fluid out and is safer. It usually requires two people though to monitor and fill the fluid.

Drain and refill though should be quick and easier.

 

I got lucky on eBay one day and ordered a dozen of them for about 9 dollars. But, the seller also had like a 40-50% online coupon. So, I ended up paying about 50-60 bucks for 12 quarts of it and I haven't been able to find a deal like that again, lol.

 

I just had the front raised high, since I was under there doing my oil pan to get my timing chain cover off. Figured I would do the trans fluid while I was there and about 6 quarts came out. I thought about dropping the pan to see what junk was on it and I think the filter is a screen and pretty easy to change. It's not RTV either if I remember correctly it's just a gasket. I think someone posted a DIY here or at another site.