Eljaffacakeo

Need help with a gearbox foible

Recommended Posts

Hello, 

 

I have an issue, as such, with my 5sp AT. 

 

I had the fluid changed in March and since then I have this weird thing happening, mostly between 4 and 5 and past 5 where the car seems tof ind an extra 500rpm. The weird thing is, I get more power from it, when it happens (mostly going uphill) I start going faster. My understanding of slipping is that you get more rpm but no increase in power (like a clutch in a manual that's buggered). So I am not sure what this could be. It was only after the fluid was changed that I noticed it (the fluid wasnt flushed).

 

Any ideas? Thanks. 

Share this post


Link to post
Share on other sites

What is the problem exactly? The revs go up by 500 rpm when you put your foot down? Isn't that normal?

Share this post


Link to post
Share on other sites
1 hour ago, Loren said:

What is the problem exactly? The revs go up by 500 rpm when you put your foot down? Isn't that normal?

 

Well, yes and no. So, if going up hill for instance in 5th gear, the revs start to drop off (as they should) then suddently I get about 500 more rpm. It's instantaneous, its like someone flicks a switch. I get a little more power then eventually the car will either gear down or settle back. 

Share this post


Link to post
Share on other sites

Wrong fluid maybe.

I know nothing about these auto’s but surely it would have to be either the torque converter slipping (unlikely since changing the fluid made things worse) or a failing clutch pack/blocked filter preventing it from applying the correct pressure. 

 

Do you get any warning lights on the dash? Worth getting the engine and trans computers checked to see if they have any fault codes present.

Share this post


Link to post
Share on other sites
1 hour ago, Andy_Mac said:

Wrong fluid maybe.

I know nothing about these auto’s but surely it would have to be either the torque converter slipping (unlikely since changing the fluid made things worse) or a failing clutch pack/blocked filter preventing it from applying the correct pressure. 

 

Do you get any warning lights on the dash? Worth getting the engine and trans computers checked to see if they have any fault codes present.

I did wonder about the fluid, but I suppose to find out I will need to change the fluid. Is it Dextron 3 for these cars?

 

I don't get any warning lights no, otherwise everything seems ok. There is a strange noise coming from the car, which I cant isolate. It appears to only be there when I am in drive and accelerating, it sounds a bit like a dry drive belt bearing or something. It reduces as I decelerate. So perhaps these are actually linked?

Share this post


Link to post
Share on other sites

When you say you get another 500rpm, do you mean the revs drop by that and you can accelerate again till it reaches the same rpm as before the drop?

If so then that should be the torque converter locking up, giving a more 1:1 ratio into the transmission. Usually happens in the higher gears. 

 

 

Share this post


Link to post
Share on other sites
6 minutes ago, SpeedySub said:

When you say you get another 500rpm, do you mean the revs drop by that and you can accelerate again till it reaches the same rpm as before the drop?

If so then that should be the torque converter locking up, giving a more 1:1 ratio into the transmission. Usually happens in the higher gears. 

 

 

No I get more revs. If you were to drive the car having never driven it, you would likely think it had down shifted. 

Share this post


Link to post
Share on other sites

What year is the car. Only thing I can think of is that the clutch band for 5th is worn and slipping. 

Any reason why you changed the trans fluid? was it badly discoloured?

  • Like 1

Share this post


Link to post
Share on other sites

 

4 minutes ago, SpeedySub said:

What year is the car. Only thing I can think of is that the clutch band for 5th is worn and slipping. 

Any reason why you changed the trans fluid? was it badly discoloured?

It's a 2008. Well I check the fluids regularly and not long after buying I noticed that the fluid was dark and starting to smell burnt so my mechanic agreed that it needed changed. He had driven it and thought it was behaving like it needed changed too. He wasn't able to change the filter though so that's still to happen. But after the change it started to behave worse. 

 

If it's a slipping clutch, surely that would mean that the car would then start to slow down and over rev, like on a manual? I have the opposite, it revs up and I can feel the extra power. It's like turning off the over-drive on the old AT boxes. 

 

Incidentally I checked the oil just there, looks good and seems to have enough. Its at the bottom "cold" dot. 

Share this post


Link to post
Share on other sites

Only thing I could think of is that the lock up is now working and when you need it it actually works. 

I know mine drops about 500rpm when the convertor locks up, and you may not notice it until you push the accelerator and then it unlocks and slips again giving you the extra rpm.

If the oil was very contaminated then it may affect the lock up clutch.

What city are you in? it might be an idea to talk to a specialist auto trans place. 

Im only going off my basic knowledge and experience. 

  • Like 1

Share this post


Link to post
Share on other sites

Ok so took the car to South Canterbury Toyota for the recall work to be done and had them check the transmission. 

 

They confirmed with my regular mechanic what fluid he used and were able to confirm that it was the wrong fluid. They took the bottom plate off and showed me the insane amount of metal filings inside and on the magnet. 

 

He replaced the fluid and flashed the TCU using the pak file from Subaru and it's still doing it, he says its slipping mostly in 1-3rd gear when under a fair amount off accel. He recommended driving it easy as he said that often the glazing on the clutch disks will get better with time once the right oil is in but he's 50/50 on whether the damage is already done. So, probably for the bin really. 

 

Wish it were easy to do a manual conversion! 

Edited by Eljaffacakeo
  • Like 2

Share this post


Link to post
Share on other sites

ouch! That sucks to hear. Did your mechanic offer any recompense if the gearbox fails? Because honestly that really is on them.  

Share this post


Link to post
Share on other sites

If it slips now, it will always slip unless you replace the 1/3 bands. Metal filings is a really bad sign, the damage is done, get a replacement gearbox, paid for by the mechanic as he put the wrong oil in it and caused the damage. 

It may work ok for a month or two, but then it will be too late as they can claim you did additional damage in those months.

 

  • Like 1

Share this post


Link to post
Share on other sites
22 hours ago, SpeedySub said:

If it slips now, it will always slip unless you replace the 1/3 bands. Metal filings is a really bad sign, the damage is done, get a replacement gearbox, paid for by the mechanic as he put the wrong oil in it and caused the damage. 

It may work ok for a month or two, but then it will be too late as they can claim you did additional damage in those months.

 

Yeah agreed. I'm going to get in touch with my mechanic and see what he says. 

 

Ironically the fluid change and the pak file have removed the 1st and 2nd gear slip and the hard change up to/down from 3rd, and replaced that with a slip! 

Share this post


Link to post
Share on other sites

Hi mate do you know what type of oil was used the 1st and 2nd time as I have the exact same 5th gear issue in my 07 legacy and which only happened once we changed the fluid I didn't have any metal filings in my fluid, we have changed it again tonight and hoping that will fix the issue 

Share this post


Link to post
Share on other sites
8 hours ago, Legacy07 said:

Hi mate do you know what type of oil was used the 1st and 2nd time as I have the exact same 5th gear issue in my 07 legacy and which only happened once we changed the fluid I didn't have any metal filings in my fluid, we have changed it again tonight and hoping that will fix the issue 

 

I'm really not sure no but the wrong fluid is the wrong fluid. Is say if you noticed it and changed it straight away, and didn't have any filings you'll probably be OK. 

Share this post


Link to post
Share on other sites
1 hour ago, Eljaffacakeo said:

 

I'm really not sure no but the wrong fluid is the wrong fluid. Is say if you noticed it and changed it straight away, and didn't have any filings you'll probably be OK. 

 

I'm rather interested to find out what they put it, as the 5eat is the BP/BL series at least doesn't use anything too special, instead just using something that meets the Subaru/Idemitsu ATF HP rating.

 

I've checked on a few oil selectors, and so far Castrol, Fuchs and Penrite all have oils they recommend. Be interesting to see what Oil supplier they use to know to steer away from!

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.