ikari

Hey guys

Wondering about the quality of 300zx's auto transmission.

For the age of this car, would a manual be preferred if trying to buy one? Thinking about things holding up over time, ease of repair, etc...

Any big differences between 300zx auto and manual? (I haven't driven any Z31's)

Do you have a preference for this car?

reddzx

Yes, if you can, buy a manual. "Automatics suck, but there are some people who still insist on buying them. All automatic Z31s used the 4N71B transmission. Change the fluid every so often, and check the level every time you change your engine oil. Also, if you overheat your car for whatever reason and it has an automatic, CHANGE THE TRANSMISSION FLUID IMMEDIATELY!!! If you don't, your transmission will blow up as a result of the fluid getting overheated in the cooler and burning inside the transmission, and this is bad. Of course, you could avoid this by putting in a manual transmission, and have more power and economy to boot! The overdrive switch in the automatics has a temperature sensor that does not allow the transmission to shift into overdrive until it is sufficiently warmed up to avoid possible damage. Level 10 makes an upgrade that will allow your transmission to hold 500+ hp. Click here for more details".

Level 10 upgrade link

4n71b level 10 upgrades

zxguy1986

Welcome to ZDriver!

I'm with reddzx on this. Haven't liked an AT since my first 5-speed experience. You are more connected with the car and the road with a manual. You feel in control. Plus, since you will be buying a used Z, you can't really tell the condition of a used AT with a test drive. My experience is that they can degenerate fast if not driven exactly as they have always been. You have no way to know what that was either. Not sure why that is, as if a used AT got addicted to one driving style or another and gets stressed out if you change it. Or maybe I imagine it.

In my experience, I would say, as a rule, AT repairs cost a lot more than manual. It's usually a replace-with-rebuilt situation in AT, guess $1500-$1800? With manual, just get a new clutch, $600? Shift right, don't grind the gears, maintain, they can go forever.

Anyway, of the current crop of guys looking for a good used Z, nobody wants an AT. Or they will buy one for other reasons and convert to manual right away ($$). Good luck with your search! Let us know what you find.

86tcoupe

the auto's were quicker when new about a 1 sec difference to 60-70 mph on :level pavement
sticks suck in stop and go 5 mph gridlock , as I drove 12 miles that way
don't get me wrong I luv a manual , but my left knee not so much these days .

ikari

Wow I know these are speedy cars but 0-60 in 1 second Just kidding

Thanks guys, I pretty much have the same thoughts... now I need to go find a junker MT car to practice with, before embarrassing myself in a 300zx

zxguy1986

Yeah, 86Tcoupe is right about stop & go traffic. When it's a bad traffic backup (more than 15 mins), I get off at the next exit and take the back roads. 5-speeds suck at inner city and backups, stop & go stuff. Your left leg and ankle get real unhappy fast.

Fortunately, I don't live in a city So 5-speeds rule for me.

zdadgeezer

I have an A/T with the Level 10 upgrade. Pat puts a larger sump a larger pump and switches to Mercon from DexronII. He tweaks the shift points and does an excellent job on the A/T. I like it because I am old and don't have any knees and just @#$% lazy. You want to Drive get a MT but to cruise A/T for me with upgrade I feel works very well.
I agree with the others as far as feel in driving is concerned, you can't compare to a MT.
But I am a weekend wine cruiser and car show goer so the leisurely pace of an A/T suits me just fine. I don't beat the crap out of it.

Level 10 Performance Transmission Systems Bulletproof Transmissions,Supercharger
He has valve kits for other Nissan apps. as well.
Yes it's pricey. Is it worth it? I plan to drive this til I die. Hopefully I'll get 27 years like my Dad did when he retired and bought it new.. The way it shifts when you get on it I'm more concerned about the rear ripping out than the tranny failing, it is crisp. Wish it had another gear or two.

zxguy1986

Great post zdadgeezer. That is all the best side of an AT.

Jmesl8er

I love my 5 speed, it's not my DD so my knee is alright.

reddzx

I agree, I'm old and like to drive an auto sometimes. I sold an nice 89 turbo auto last year that I did the Level 10 upgrade and it was as you described. Quick, crisp shifts with no lag. I spent about $1800 for the upgrade and a rebuild. I also own a 5 speed car so it was having the best of both worlds.

zdadgeezer

You know if one of these Z geeks came up with a drivetrain swap that would update the Z31 (paddle shifters etc...) I love the body style, if I could put it on an updated chassis I might put off retirement a day or two to pay for it. I don't have the skill set to do it myself, or the equipment. But I'd be interested in seeing it done or even help wrench on something like that. Well best stay on topic. Sorry about that, I like daydreaming about the Z.

Qaanaaq-Liaaq

I’m an original owner of a 1984 turbo automatic. And I’ve never had a problem with the automatic transmission.

Any big differences between an auto and manual? Yes, the biggest difference is that an auto is automatic and a manual is manual. Sorry for the circular definition. A z31 is a sports car so yes, most people are going to prefer a manual because they want to shift gears themselves as part of the driving experience. I live in a big city with all day stop and go traffic and a stop sign or light at every block. I ordered an automatic because it would basically be too tiresome to have to manually row through the gears all the time.

Generally speaking, I think automatic transmissions cost more to repair than a manual but that goes for any car not just a z31.

z31 automatics also came with a transm. fluid radiator. It’s in a separate section of the engine coolant radiator.

In the z31 era, manuals got better gas mileage than automatics. But I don’t think it’s much; maybe 1-2 mpg difference.