3N71B 2nd gear shifting problem

[josh_t]

I've gotten my B on the road and been driving it around for about 3 days, almost non-stop. Really nice MPG for an auto. We did go a little hard on it most of the time, but no drop shifting, burn-outs, etc. We took it on I-20 3 times total, going about 65-70 the whole time, rides fantastic, no pulling to the side, no play in the steering, no vibrations or noise from the brakes, no bouncing, or wierd noises from the suspension, just awesome ride and very acceptable performance for 80hp turning an auto. The shifting was nice and firm, but not harsh or noisy or anything like that. Then after we got off of a two lane highway going about 55, we came out of the red light and first felt just fine, like normal, then second comes and its a very slow, very soft, shift, it took about a whole second to fully engage. The last upshift into second before we got home was kind of wierd sounding, a high pitched whine, or very mild squeal came out of it. If i could describe the sound, it would be like eeeeewwwww. My first thought was the material on that band has worn off and its getting close to bare metal now. Shifting in to third is just fine. Shifting down into second manually and then down into first manually feels firm still. The trans was still hot since we drove for 30 minutes or so home, so i pulled the dipstick while its idling in neutral and its right where it needs to be, i wipe it off and there is a nice bright red/pinkish color to the fluid, but it also wiped some dark gray/black stuff off too. Its very fine, i can't even see particles, but from my limited knowledge of automatics, that could possibly mean band/clutch pack for 2nd is going out? I'm actually somewhat satisfied with the auto for now, i got over my little need for speed problem, and its still a blast to drive around since the handling is tight on it. I need to know the quickest, cheapest way to properly fix it, whether it may be swapping a manual in, or changing the bad band, or any other ideas.

 

EDIT: one idea that i just thought of that would be very fast and very cheap, could the modulator be stuck in the high vacuum position causing it to shift like i'm barely pushing the gas? We did just let out of the gas and coast down some hills on i-20 going 65, which is about 3500rpms, and thats a lot of vacuum coming on all of a sudden. We did that frequently actually, since coasting with a big exhaust makes that cool rumbly sound.

[datzenmike]

See how it is when it's cooled down.

[josh_t]

i'll try that tomorrow. i've been looking around and i've seen some sites saying a clogged filter can do it too, but i think that would affect at least all the upshifting if not downshifting too. i hope its something easy.

[datzenmike]

Well if you change the filter you can adjust the band. The piston stem should be torqued to 9-11 ft. lbs. then backed off two full turns and the lock nut tightened to 11-29 ft. lbs. You had better confirm this setting.

[josh_t]

i dont think i'm gonna change the filter unless i totally rule everything else out. i tried driving it after close to an hour so the fluid would just be warm, and i'm not sure it did better. i'm gonna actually take it for a real short spin tomorrow and see if it'll shift right under a little bit of a load because its actually going to tell me whether or not its working properly, you cant hardly feel it shift into second most of the time if you are barely pushing it. first into second used to be a good solid shift when you were really trying to get up to speed, like a stop sign before an entrance ramp for example. i'm hoping its fluid or modulator related. if it comes down to rebuilding the automatic transmission, i'm really going to look into getting a 4 speed swap for maybe around $100 if possible. i know for sure i can swap a manual in it but i seriously doubt i can fix an auto right, and the $116 for the master kit would be a waste if it messed up soon after i rebuilt it.

[datzenmike]

My L18 710 is hardly noticeable into second with light throttle. So light I've missed it and when it shifts into 3rd I think it's second and keep waiting for it to shift. Very noticeable if you give it some gas and like a hammer if you floor it from a stop.

 

I think the modulator only helps select a shift point based on manifold vacuum. High vacuum means light throttle so it up-shifts ASAP. Low vacuum means heavy foot and holds it in that gear until the governor decides.

[josh_t]

it determines the shift strength too. i actually unhooked mine a long time ago and tried it and it shifted a little later but it shifted really hard into second. that was only one hard shift though, about 9 months ago. it still shifts very soft after an hour or so of shifting like you just were driving real easy in D, when i shifted it manually, i'll find out tomorrow if it slips when i get on it. is there any type of additive or fluid i can use to possibly prolong whats left of this thing?

[josh_t]

Its NOT a temperature problem. i just drove it and it was just the same as when it was hot. i couldn't even tell it shifted into second at high rpms. it feels fine whenever it actually decides to be in second. maybe i'll just drive it around and just be easy on it in second. if second goes totally out, i still have first to get me home. and i can wind out first and force it to go straight to third, by shifting to D and letting off the gas. So i wouldn't be stranded without second, it'd just be interesting to get it home.

[josh_t]

well my transmisson fluid might be low. i thought that it was at the right level, but it seems that when its running and warmed up, i'm not seeing it on the dipstick. i pulled it before i ran it today and it was burgundy colored and had a somewhat burnt smell to it. i usually see a faint pink when its warmed up, so i'm thinking its low, since it wasnt burnt before, and it doesnt show up burgundy when its warmed up. i'm assuming that means it gets pulled into the pump and torque convertor and the valve body when its running and it really does end up being low. i also see a decent amount of fluid around the back of the transmission, and its all over the linkage and transmission mount. same thing at the rear end. so i'm thinking i need to change my rear transmission seal and the diff seal. and both need fluid/oil. just my guess. i'm definitely open to anything else

[I'm BLUE]

Change your fluid and filter (only benefit) if you're going to keep the trans.

 

Many modern cars require transmission's fluid to be checked when hot.

 

If your trans goes out you'll have no way of knowing what will/wont work...

 

I like Lucas additive in general ... but trans stuff ... it's a temp band-aid at best if your trans in rougher shape.... just changing fluid is best.

[josh_t]

i'm thinkin since its 3 quarts for the whole thing (11.8 pints according to chiltons manual), i'll just change it like you said. If it fixes it, i'll get a $25 dollar cooler from jegs to put on there so this doesnt happen again. I have a 192 degree thermostat in mine so the coolant will average about 12 degrees hotter than stock. and since you generally want your trans fluid between 175-200, a cooler will be beneficial. i took it out today for a quarter mile drive and it randomly shifted into 2nd normally, so maybe it IS just a fluid problem.

[ggzilla]

The most common problem is OVER-filling. It must be checked when hot, after driving for 15 minutes as the fluid expands a lot. And the difference between H and L lines on the dipstick is something like 1/4 quart. Be very careful when adding that you do not overfill it.

[josh_t]

well it is overfilled. its just to the top of the little bend above the h, so its probably less than half a quart over.

[josh_t]

i read an article about a guy doing some experiments on a 4L60E and he said when he did tests using too much fluid he noted that it would behave erratically because of unstable fluid pressure. And he says the cause is the foaming from the gears churning the fluid. mine isnt churning it, but i did see a whitish, almost foamy consistency to the fluid the other day, so maybe i just need to change the fluid and put the right amount in it this time. Does this sound like a probable cause?

[ggzilla]

half a quart over is a LOT over. Normally when adding, it's like a 10th of a quart at a time.

 

Don't bother to change the fluid. Just drain a little, the AFTER GETTING IT HOT -- drive for 15 minutes -- make sure it's between L and H lines. If so, don't add any, it does not need to be on the H line. Just in between L and H.

[datzenmike]

Easiest way to drain it to loosen one of the coolant lines from the rad cooler and let it idle a few seconds. Pour into a container and examine. It should be RED not BROWNISH OR BRICK colored. Up to you, but if you can see particles, that's clutch material that been burned off the facings, I would drop the pan and dump it out and replace. This just leaves the fluid in the torque converter. When the transmission is refilled, pull the coolant line off the rad and idle until a quart has been pumped out an shut off. (you don't want it to run dry) This is from the converter. Replace the amount removed with fresh and repeat until fresh ATF comes out. (you won't get it all because the new mixes with the old but you can flush most of it out) Carefully refill as ggzilla said 'between the lines' when warm and running.

 

By all means get an in line aftermarket cooler!!! Good idea. Heat is what kills automatics.

[ggzilla]

All B210 with A14 comes with an automatic transmission fluid cooler from the factory. No worries there. The 3N71B can cope with the torque from a six-cylinder much heavier car, so behind the A14 they almost never go bad.

[josh_t]

ok. when i looked at it today, it was still pretty red, so i'm thinking my fluid is still in good shape. and from what i've read, the churning would make air in the fluid that could cause erratic hydraulic pressure. i'll be under the car anyway tomorrow flushing and refilling my cooling system, so i'll do this around the same time. From what i've read, 2nd gear going out is the first sign of a dying jatco, though. So i'm still a little worried. I also seen a reference of a ford granada with a 250c.i. i-6 coming stock with a jatco so i'm not doubting their strength anymore. Wouldn't the 192 degree thermostat cause the transmission to run noticeably hotter than normal?

 

EDIT: this new job will have me bringing about 1k home a month so a $25 cooler from jegs seems like good insurance whether it needs it or not. i've never heard of a transmission failing because it wouldn't get hot enough. I forgot to mention that i am somewhat hard on it, so a cooler wouldn't be too far out of line.

[ggzilla]

Yes, stock temperature is 82C/180F, but the 88C/190F was optional for cold climates (heater runs hotter). Either way, it keeps the transmission cooler than internal temperature. So it is good.

 

Additional cooler is a waste of $25. They almost never go bad on B210s, and not due to heat or "driving it hard". Low fluid level is the usual problem, caused by either leaking gasket or a ruptured vacuum modulator -- or by leaking lines fittings (such as with extra cooler). One thing you can do to abuse the transmission is to hold the brake and floor the engines. This should only be done for a few seconds, longer can overheat the transmission, but you don't need another cooler for that (just stop doing it).

[josh_t]

haha. i cant say i havent "boxed it up" before. its been a long time and on the same fluid which i'm now almost certain isnt burnt. So very little, if any harm done. My temp gauge stays just below the lower hot line while on the interstate and lower than that at lower speeds, and that's with an estimated 17/83 antifreeze/water mix. It'll be 50/50 tomorrow, so i think that'll drop a couple degrees. The water's not the clearest stuff i've seen.

[ggzilla]

A couple of degrees, even 20 degrees won't make any difference to the transmission.

[josh_t]

well thats good. i'm not worried about the water temp being that high either because it runs better all around at that temperature than it does at a lower temp. And i've left the timing 5 degrees advanced from stock with no pinging whatsoever at any load or temperature. And this is on 90-something degree days here in GA. So this little transmission deal is the one and only problem i'm having. I will tell you that you guys were right and once i drove it, i decided that it really was a fun car to drive despite what the numbers and specs say. the mpg is great, and it has really tight handling for its age, even with a 240 pound guy in the passenger seat. and it gets up to whatever speed you need it to be in a timely manner, so there is nothing i can really complain about.

[josh_t]

so i changed my coolant, and flushed everything. it dropped my normal operating temp from right at the fat line below the H, to just above halfway. i was gonna pump some tranny fluid out but as soon as i started to get back under there, it started to rain. but i have a question anyways, Which hose is the one pumping and which one is the return line? and how long would it take to pump a half quart out at idle? i dont want to accidentally pump half the fluid out. maybe i'll rig up a remote kill so i can stand and watch and then kill it when it gets where it needs to be.

[datzenmike]

I believe the pass side comes from the auto, driver's side return.

 

It doesn't come out that fast, at least at idle. You should be able to watch it and still have time to turn the key off.

[josh_t]

ok. that makes it a little easier then.