Help - geabox trouble don't want to scrap the car

[hollo]

Hello , Just wondering if any can help me with some pointers or advise ?. I've got a 2005 GS300 ( the first of the mk3 ) , and I love the car.  It's the 3rd one I've owned , and I just seem to keep coming back to them as it's such a wonderful car to drive.

Anyway , it's got 142,000 miles on the clock , but I've got a serious transmission problem . At first it would not change up into top as the revs were too high for the motorway speed I was travelling . Now it's got worse , as it feel like it's pulling away in 2nd gear  , and there is no reverse gear any more . You can 'feel/hear ' the gear engage ( I think ) but there is no drive . Also the VSC warning light and stability control light also came on. Apart from that it still drive like a dream and the rest of the box is fine.

I took it to a local-ish auto 'specialist ' , who for £50 + vat gave me a list of the fault codes and cleared the warning lights . He sucked his teeth and said it would be expensive and he'd ring me back with a price for a recon gear box - but he's never bother to ring me , so sod him if he does want my money.

Anyway the three fault codes are , P0751 , P0761 , P2714 .

Could any please help me ? . i don't really want to scrap the car , anyone any idea of anyone who could help with trying to fix it ? . My only thoughts are that it may be electrical as opposed to the actual gear in the box , due to the number of faults ? , but I could be wrong.

Sorry for the long post , and thanks.

Mike  

  

[JamesIS220]

No idea on the codes but have you checked the gearbox oil level?

What colour is it? Black/dirty,  Does it smell burnt?

When did you last renew the gearbox oil?

James.

[Mihanicos]

Hi,

P0751 refers to Shift solenoid A performance or stuck

P0761     "                      "           C              "

P2714  refers to pressure control solenoid D or stuck

It seems that you may have debris in the valve body which inhibits the solenoid operation and the oil filter may be clogged The first thing I would do is to change the transmission oil filter and the oil. They are recommended to be changed according to a maintenance schedule, depending on the service conditions the car is operated under. 

The solenoids are mounted on the valve body and they operate to give the right combination of various clutches so the right gear is selected according to the transmission ECU commands. Under normal circumstances a good cleaning of the solenoid plungers and the channels they operate through, should restore a seamless gear shifting throughout the range. Normally, the valve body is removable having removed the oil pan first.

Chris.

 

[hollo]

Hello , thanks for the replies . The 'specialist ' who i took it to said the oil was OK for the level , but it was dirty . He didn't offer to change it and the filter , he just recommend  full gearbox recondition .

Can anyone recommend a garage who would be able to change the fluid/filters and clean the solenoid plungers ? . As when this first happened the local trusted garage I took it to said they didn't touch auto boxes and I went on their recommendation of the 'specialist '

Are there any Lexus gearbox specialist anyone can recommend from experience ?. I'm in Maidenhead Berkshire . I've had a quick look but couldn't find anyone local-ish who advertises these services.

Thanks again

Mike     

[m4rkw]

If you just want a drain+fill you could take it to Toyotec, they've been great in my experience. I don't know if they can do a "full gearbox recondition" which I'm guessing means a rebuild, but the solenoids are external so if one or more has failed then I think any competent garage should be able to take care of that. Even if you do need a full rebuild I'm sure they could recommend someone.

[Mihanicos]

I missed out recommending a drain and filter change, like another member has already mentioned.  Fill the transmission with new oil, use the recommended by the factory, do not try anything better  cheaper, synthetic..... There is a high possibility that the transmission will recover.

Chris

[m4rkw]

Yep definitely worth a try. A friend of mine had a Porsche Cayenne that had 130k on the clock and the transmission had never been serviced. It started shifting badly and he took it to a gearbox specialist and they did something called a "power-flush". I wouldn't normally recommend flushing any gearbox but in his case it worked and was still working fine a couple of years later. Probably just had some dirt lodged somewhere.

[steve2006]

Could you post up the “Specialist” who looked at your transmission so other members could avoid given the teeth sucking and non communication?

There appear to be several other specialists in your area maybe take a look at their reviews and try another one.

The solenoids do tend to get gummed up in an old fluid situation and as other members have mentioned a fluid flush and new filter can improve matters. The actual solenoids can be accessed by removing the sump at which point they can be removed, cleaned up and tested for functionality.

Another solution would be to fit a known good secondhand transmission from a breaker.

Image below shows the solenoids at the top.

[hollo]

Hello , and thanks again for all the help . The Company never even bothered to call me back , and i'll never use again was 3D Transmissions in Tilehurst Reading.

I've had a cunning plan or two, 

Plan A - I've found a garage in High Wycombe who will change the fluid and filter and possibly have a look at the soleniods  , so I'm really hoping that'll fix it.  it's booked in for Monday next week.

Plan B - Another more local garage in Maidenhead said he can source and fit a secondhand box for £900 - £1000 . I'm hoping that I'll not need plan B.

i'll post up on hear how I get on.....

Thanks again to everyone for all the help and advise.

Mike 

[m4rkw]

B sounds suspiciously cheap, will they give you any kind of warranty on it? Will they even warrant that it works correctly when you pick the car up? If so you might want to spend some time reading up on how to test drive an automatic to make sure it’s shifting correctly, not slipping and going into lockup when it’s supposed to. 

[Werewolf1976]

My 2cents, the transmissions used in the GS are usually quite robust - this makes the used gearbox route (rather than reman'ed) viable

Shop around a couple of wreckers 

[woody_k82]

Grab a bru, this is a long post but I hope you will benefit from my experience/ mistakes!!!

I had a similar issue "Check VSC" but with code P2757 - I think I have fixed it, taking 3x oil changes (9l of Toyota WS ATF @ £15 p/l), a new SLU solenoid (£250 from Lexus) and 2x shudder fix (£15 from eBay, friction modifier), 2x AT filters and gaskets - the gasket is not reusable and must be changed and you must use sealant to mate the sump with the AT unit.  And about 6 hours in total of ramp time (3 hours each time @15ph) - first time a mechanic pal did me a solid.

In line with previous comments of dirty or blocked solenoids, the new solenoid was fitted with a filter.

I believe the issue was caused due to poor maintenance - the oil looked dark, like it was burnt - so I have to accept that I may have delayed the death of my gearbox and not fixed it completely but it seems to be pretty much as smooth as it was less the check VSC.

1st attempt - drained the AT changed the filter and ATF - the code and the check VSC came back, now with a shudder too, noticed when going up gentle inclines! And in the extreme cold, the car almost had zero power pulling away - after a couple of minutes it pulled away fine.

2nd attempt - drained the AT, changed the SLU solenoid and refilled - check VSC disappeared but the shudder remained and the problems with pulling away from a cold start in the extreme cold (1C or below) remained.

On attempts 1 and 2 - I followed some advice to get ATF temp upto 40C and then allow the expanded fluid to seep out of the overflow - when it stops, seal.

3rd attempt - drained and refilled with a new filter and also added 2x tubes of shudder fix, I added 3l of ATF and sealed the tranny without going through the overflow procedure - ALL PROBLEMS FIXED!!!

The ABSOLUTE key was measuring how much ATF came out on attempt one, which I failed to do but I know it was roughly 3l.

Other lessons which might help -

- a bracket secures the two exhaust pipes at the front end of the AT unit which obscures some of the sump screws - you might get away with removing one side and just pulling it down and out of your way - those nuts and bolts on the exhaust can get pretty corroded for obvious reasons, in the UK!

- use only the recommended fluid for your transmission - I've learned this from painful experience messing around with a ZF transmission on a Jag S-type in the past.

- YOU MUST measure what comes out of the transmission - allow it to cool before measuring volume, BEAWARE - when you remove the AT filter more fluid will come down!!!! Be ready to catch.

- These Units are not opened, and come as sealed Units, so open the fill cap before you drain or you'll be totally screwed if the fill is stuck!!!

- You can do this job on your drive BUT I would urge you to rent a ramp, it can get messy.

- spend £15-20 on a decent hand pump, you'll need to hand pump ATF back in to the Unit.

- watch this video first, it points out the key stages for this job!