240sx auto tranny Q.

[-usmd-180sx]

Alright, well this might be a little hard to describe, but bare with me folks. I'll try to explain it the best I can.

When I drive my friends 240sx (s13), which has a auto transmission, the car runs decently half the time. But then this problem kicks in. Generally on the freeway, after the transmission has shifted to its final gear for freeway crusing, around 45mph, the car doesn't accelerate anymore. At the same time, the car buckles really hard. Then the Rpms rev up, and once the speedometer reved up as well with the rpms, and the car generally loses speed. I had to dump it in 3rd or 2nd to actually get off the freeway, but slowly. A further note, if you forcefully accelerate the car, in the condition, the car just bucks really hard over and over again without anything improving

He got his tranny replaced about 2 yrs ago because of the same problem.

Right now, we are both stumped about what could be causing this..

If any similar occurances happened to anyone, that would be very helpfully to hear what caused it and what solution u took.

Didnt know if this should be chat.. or tech.. or both.. so if needed.. please move to appropriate thread

[projectRDM]

Could be a lot of things within the transmission, but the million dollar question is when it was replaced, was the radiator cooler flushed thoroughly? If not, the new one is on it's way to being trashed.
When an auto dies, whether it's a gear, solenoid, the pump, whatever it may be, the particles and trash coming from the damaged piece are picked up in the fluid and run through the pump and into the cooler. After replacing the transmission that trash that has collected inside the cooler immediately begins to wash back into the new unit. Unless he's stuck to a good break-in schedule and changed the filter regularly there's debris slowly caking inside and it's a bet that's causing the problems he's having now.
Every car I've ever gutted with a 'new' automatic has seen more than one, or the one in it is already dead. Best bet is to add an external cooler and bypass the radiator completely, or at least replace the radiator with an OE comparable unit. That is after you replace the transmission.

[m0rex]

Or how about you do a 5 speed swap. Damn i just had to say it.

[-usmd-180sx]

lol motrex, its his daily.. and he is lazy..

And your answer intrigues me R240NA.. it happenes occasionally.. and sometimes happenes 4-5 times a day.. And after it happenes.. it runs like a champ!

You think it can be saved before the trans is totally gone? Flush the radiator.. and do a trans flush as well?

Might see a reasonable difference.. What ya think??

[projectRDM]

Do it now while it's still feasible. Take the radiator out first and flush it, high pressure water backed with air *might* clean the cooler out enough. If the fluid coming out looks anything less than a perfect red, buy an external cooler.
After that's covered have the transmission flushed by a competent place. You can pull and flush the lines but you won't get into the pump very well that way, so let someone else do it with a real machine. Once that's done, change the filter immediately, and then change it again after 1k miles. That should get most of any debris out and possibly prolong the life a little.
And if it ever needs replacement again, pull the pan on the new one and inspect it before buying. I've seen "new" units look just as bad as the one coming out. Since autos are generally treated as garbage by people swapping they're not going to take the best care of it.

[ROGER]

the same thing happened with my 95 last year. russ has the right idea about having it flushed with a real machine. as far as mine, new beefed tranny installed, system flushed of old fluids, and i went with a tranny cooler as well. it's been a year, everythings doing fine. with mine trash would make the bish "stick" on the highway, but after it passed, ran fine like nothing was wrong. kinda like a kidney stone i guess, lol

[-usmd-180sx]

lol.. roger.. same simptons that i stated that you encountered?

[ROGER]

yea man, same basic symptoms except i also had a check engine light come on as well.

[jd-17]

seriously i had a problem with my auto tranny and after replacing 2 times im just gettin a 5-speed swap even if it is a daily driver. it just makes life with a 240 a whole lot easier and more fun

[-usmd-180sx]

:stupid:

but yea.. seriously.. it does... Just my friend might go through his 3rd tranny trying to learn how to drive it.. lol

[jd-17]

it would be well worth it and no more worrying about an auto tranny

[projectRDM]

it would be well worth it and no more worrying about an auto tranny

If it's installed correctly and not abused there's really nothing to ever worry about though. It's the people who never change the filter, drive it like a manual, and then swap a new one without flushing the cooler who continually have problems. Preventitive maintainence goes a long way with an auto transmission.

[jd-17]

If it's installed correctly and not abused there's really nothing to ever worry about though. It's the people who never change the filter, drive it like a manual, and then swap a new one without flushing the cooler who continually have problems. Preventitive maintainence goes a long way with an auto transmission.
not really true..mine was well maintained by the previous owner and as soon as i got it i had a full check up done. I changed the oil filter and the oil, replaced the rack and pinion,filled the power steering fluid and it still broke down. My auto is getting ready to be pulled out this weekend for the swap.So do what you want but auto is not the way to go.......

[jayka]

yea my tranny has the same problem, i already have a manual tranny cuz i know it would be better then trying to work with an auto

[ROGER]

It all really depends on what u prefer. my car is a daily driver. in my case i didn't like shifting gears daily anymore. i used to be into toyota celicas and supras(rwd mid 80's versions) and all of them were manual. then i decided i wanted a 240 in 2000. i liked the reliability of the cars(my mom has had one since 93), and automatic was no problem for me. i do think if u'd prefer a manual and bought an auto cause it was a good price or something, manual swap when the auto eats it is sound judgement. if u gonna spend the money anyway, may as well do it without regrets if that's what u want.

[-usmd-180sx]

yea.. but getting off topic :nono:

Friends gonna flush this weekend, and i shall post results.