Auto Box Problems

[Davezj]

Hi All,
i have an Auto box problem!

grinding noise in 1st gear when moving forward at low speed 10 mph
grinding noise in 2nd gear when moving forward at low speed 15mph
grinding noise in 3rd gear when moving forward at low speed 20mph
4th gear is normal, no noises, grinding, or anything abnormal.

going from 1st to reverse jerky change.
going from reverse to first jerky change.

ATF level is fine, but slightly brownish/off red colour.

all i can think of is, it is the first planetry gear set as it only seem to effect the first 3 gears and each planetry gear set has 3 gears depending on which cog you stop turning. see animation below

http://auto.howstuffworks.com/automatic-transmission3.htm

our auto box must have 2 sets of gears though.

If anyone has anyother thought on the issue i would be interest to know.

[elnevio]

Dave, very similar noises to those that mine made. The pitch of the noise did not change with speed or which gear (of 1, 2 or 3) I was in, it only got louder the faster you went. As soon as fourth or fifth was engaged, the sound disappeared and was as if all was normal. The sound sounded like exaggerated road noise to me. It also did it if you put the box in neutral. Going very slowly (i.e. no accelerator input) also made slight, but horrible, 'broken diff' kind of noises. Otherwise, I found the fluid level to be fine, the condition of the ATF on the dipstick was okay, and it generally changed like normal (didn't try anything under WOT or even decent load though - as much as I wanted to launch it to see how much it would poo itself! :D). I did get a couple of clunky changes into 1st on occasion.

Something had been chewed off inside the box. There were no apparent signs of broken wave spring, although there was certainly metal chunks in the box, and a couple of cogs had little bits missing! Still, it did manage 70mph for all of the 90 mile motorway trip to Nick Mann's. He did show surprise that it made it there! :)

Whilst we never found out exactly what was broken (time pressured, as we were!), I would be surprised if this is not the same problem as I had.

[Davezj]

Thanks for the info nev, itdoes sound very similar to your experince.

I do have a spare gearbox to fit, but it has been sitting around in the shed for he last 3 years or so, so i am not sure if it is still good or not. I fear things might have dried out inside the auto box due to there only being a small quantity of ol left in it.
Oh well it looks like i will have to bite the bullet at some point and change it.

I did a bit of driving back wards and forwards out side the house and the car made some grinding and cruching noises then went quite again, and no more jerky changes from reverse to drive.
I think i will go for a very short drive and see what happens.

[Davezj]

Well i took it out for a very slow drive and unfortunately my original prognosis was correct, horrible grinding in 1,2,3, silent in 4, and jerky changes from reverse to drive and back again.

it sounds light i am dragging some chains down the road under the car.

so i think the auto box is FUBAR inside.

now what did i do with that new torque convertor seal i bought 2 years ago to swap on the auto box i have in the shed, i would be foolish to swap the box over without swapping the seal first.

[Davezj]

well i swapped my auto box, what a pig of a job.

still have issues though.

[lateshow]

i've changed all the engine mounts, flushed the box with 12 litres of diaqueen and still some imperfections. Oil is light red now, not brown even a little bit. Like when swithchin on or off drive or reverse seems that there is a very big amount of power engaging somewhere, one could say jerky yes. And sometimes shifts are still little too rough. ATF level is a little over hot as it should be when checked. Planetary gear keeps some noise with smaller gears and especially when its cold. My friends legnum's planetary gear keeps even more noise (i've listened the engine through headphones for knock) even in bigger speeds but the box changes gears better, that box has been out of car once, because of the the input shaft gasket leak.

[Davezj]

i've changed all the engine mounts, flushed the box with 12 litres of diaqueen and still some imperfections. Oil is light red now, not brown even a little bit. Like when swithchin on or off drive or reverse seems that there is a very big amount of power engaging somewhere, one could say jerky yes. And sometimes shifts are still little too rough. ATF level is a little over hot as it should be when checked. Planetary gear keeps some noise with smaller gears and especially when its cold. My friends legnum's planetary gear keeps even more noise (i've listened the engine through headphones for knock) even in bigger speeds but the box changes gears better, that box has been out of car once, because of the the input shaft gasket leak.

you do realise the auto box might take as long as 500 miles to settle down and go back to being silky smooth after the battery disconnect. it is the fuzzy logic in the auto box ECU relearning the shift points and shift action. It ma also take a little while for the new ATF to undo some of the damage the old warn out ATF had done. e.g. on the clutch packs which can get varnished up whch will make changes less than perfect. that is why most people will recomend AMSoil ATF as it includes cleaning agents and anti varnishing magic with it's make up. It will take time for these additives to do there work, so you can't expect instant results.

By the way my issues were no drive in D and car would not start in P park.
Starting in park now fixed and i am sure a different ECU will fix the no drive in D.

[Ryan]

I think that 500 miles is waaaaaaaaaaay beyond expectations Dave.

[Davezj]

my last VR4 took an age to settle down completely, it took about 50 miles to get rid of the inital slugish/jerky gear change and another about 450 miles to return back to full silky changes. i thought it was buggered when i first replaced the battery.
well that is my experience.
If this guy has been driving around with bad ATF for ages then it could take 1000's of miles to undo the damage with the cleaning agects in the ATF doing there stuff. and he might even need a second ATF change if when he rechecks the colour in about 3 months time and it brown again due to all the crap it has stripped of the unside of the auto box.
There is no point in get did of the crap from the inside of the auto box just to leave it in the atf inside the auto box.
it all depends how dirty the auto box was in the first place.

The auto box could have been squweeky clean inside and it is just the auto box that is bad.
but personally i would not do anything with it (as long as it does not get any worse) until 500 miles in.

[Davezj]

just thought i would round this off with with a bit of info.

got my car sorted changed gear box.
lost drive in D.
changed ECU to match up with auto box
everything work fine again

[elnevio]

Everything? How are the gearchanges?

So what Engine ECU / Gearbox ECU / Gearbox combo do you have now?

[Davezj]

1. my original config ECU MR367177 Auto Box W5A51-3-E6B (OWC).

2. Swapped auto box from W5A51-3-E6B (OWC) to W5A51-3-E6A.

3. Lost drive in D.

4. Swapped auto box ECU from MR367177 to MD761988

5. i can get drive in D and everything works perfectly.


so i have effectively swapped form a late model PFL (with TCL) 1998 auto box (OWC) and auto box ecu to and early model PFL (withTCL) 1996/97 auto box (non OWC) and auto box ECU.
If you change the model of gear box you have to change the ECU to the matching ECU that corisponds to that box.

if you have a late model PFL without TCL then you need to change the auto like for like, e.g. W5A51-3-E6B (OWC) swap for a W5A51-3-E6B (OWC). This way you will not have a problem with the exchange.


More info in this thread
http://www.clubvr4.com/forum/showthread.php?59469-boost-solenoid-gear-box-ecu/page3