Auto tranny torque monster

[h23]

I'll start off by saying hello and I'm pretty new to this forum. I have an auto 1995 240sx and a 5 spd 1987 rx7 Turbo II.

Now what i would like to do is to build my daily driver (the Zenki) while keeping it reliable and automatic. I'd like to see around 220 - 230whp. Now I know a lot of different setups can get me there reliably, but what I would like to know is if there any mods to the auto tranny I should be planning to do? Feel free to list some setups which would be good for my power goals, but please also note that I am only 17 and I need this car to get me through college fairly reliably. My main concern is what should be done to my tranny to keep it from shitting the bed. I don't beat on my car day in and day out, but I would like to track it a few weekends a month.

Thanks for any and all help,
Matt

[projectRDM]

The auto unit in the 240SX is the same as used in the 300ZX NA. It's fine with the 220 or so the Z delivers, plus a little more, so you're fine. If anything, change the filter and fluid once every two months until you've fully flushed it (you can't get but maybe 60% of the fluid out during a filter change), or have it put on a pump and run new fluid through it.

Do NOT unplug the dropping resistor like every kid online will tell you to do. It maintains line pressure in the transmission, unplugging it greatly increases wear on the bands and gears.

[Pitchblack98]

I was wondering this same thing. I also have a 1995 Auto 240sx. I think mine is on its way out though. It shifts pretty hard from 1st to 2nd. Its a lot worse when its cold, but still does it after its warmed up. I might try changing the fluid and filter every couple of months to get the old fluid flushed out and see what that does.

Im saving for a SR and 5 speed swap. I want to get it all done at one time and not have to worry about anything.

Thanks for the great info R240NA!

[projectRDM]

Fresh fluid does wonders for an automatic transmission. ATF breaks down thermally pretty easily, plus because it has detergents additives it picks up a lot of trash/varnish and carries it around inside the case until it's drained. That alone makes it thicker and heavier, especially when cold.

[Pitchblack98]

I will probably change mine with a 70/30 mix of Nissan ATF fluid and Mobile 1 synthetic or something simular.

I had the auto tranny going out on my old Honda Accord and had the dealership check it. My brother-in-law is the parts & service manager at the Honda dealership here so they treat us pretty well and I would believe what they said about the car. They told us the tranny probably wouldn't last another 10k to 15k miles. While researching the problem I found that it was pretty common with 92 to 96 auto Accords and Preludes. I read somewhere that I could mix Honda's ATF and some Synthetic ATF and it might last longer. I figured I had nothing to lose so I mixed them and started changing the fluid more often. I put another 115k miles on it while changing the fluid every 25k miles or so without any problems at all. Someone finally rearended the car while my wife was driving it and insurance totalled it. I would of loved to see how much further it would of went before it finally burned up.

After mixing the ATF and changing the fluid it shifted like butter with the occasional hard shift or jerk. I have no complaints about it. It saved me a ton of money in the long run and we got more from the insurance company for the car that I would have from a dealership trade or private sell. I didn't want to sell it and pass the problem along to someone else.

[240tek]

A lot of us cheap bastards will retain the Auto trans for the simple reason we cannot afford the swap costs (yet) while being held back by the RE4R01A slushbox. It's a relatively beefy trans, from what my buddies at -www dot KA-T dot org- will recommend is using Tractor fluid "recommended for wet clutches" important that last part, dont know if they make it any other way. I currently have Royal Purple, and a bottle of this really thick Lucas Trans stuff. Every now or then you'll want to flush with some Seafoam made for Transmissions.

You can do things like upgrade the Torque converter for a greater stall speed, allowing you to rev up off the line granting better launches. You can also swap the valve body with one that has been modified, this allows quicker and more efficient gear changes. Finally, your clutches and the rest of the trans can be rebuilt, keep in mind this all costs money.

RE4R01A's are cheap, usually 50 bucks or free even. 225 is easy to attain and hold with the stock beast, it gets interesting with 145K on the clock.

[S14DB]

I will probably change mine with a 70/30 mix of Nissan ATF fluid and Mobile 1 synthetic or something simular.

I had the auto tranny going out on my old Honda Accord and had the dealership check it. My brother-in-law is the parts & service manager at the Honda dealership here so they treat us pretty well and I would believe what they said about the car. They told us the tranny probably wouldn't last another 10k to 15k miles. While researching the problem I found that it was pretty common with 92 to 96 auto Accords and Preludes. I read somewhere that I could mix Honda's ATF and some Synthetic ATF and it might last longer. I figured I had nothing to lose so I mixed them and started changing the fluid more often. I put another 115k miles on it while changing the fluid every 25k miles or so without any problems at all. Someone finally rearended the car while my wife was driving it and insurance totalled it. I would of loved to see how much further it would of went before it finally burned up.

After mixing the ATF and changing the fluid it shifted like butter with the occasional hard shift or jerk. I have no complaints about it. It saved me a ton of money in the long run and we got more from the insurance company for the car that I would have from a dealership trade or private sell. I didn't want to sell it and pass the problem along to someone else.

Worst Idea Evar. Only use Non synthetic ATF fluid in your Auto. Preferably the Nissan Matic-D ATF fluid. They clutch material in the Nissan's does not like synthetic fluid and will glaze them.

The Nissan Matic-D ATF is a low ash fluid that increases clutch pack life by having less contaminates.

The Best thing is to change you fluid every year to two years(every 4th motor oil change).