Hi guys, I own a 1985 VDP and on our way back from Melbourne to Canberra last week the GM180 auto gearbox gave up the ghost. As we were near Sunbury, I got the car to Sunbury Automatics who supplied and installed a reco box. The problem is that the reco box change sequence seems to have a mind of its own. Under moderate accelleration, it changes from 1st to 2nd at around 25kph and top at 75-80kph. At 60kph it continually wants to hunt between 2nd and top. The changes are quite harsh when it hunts. I rang Sun bury Automatics who said it was just the kickdown cable that needed adjusting. I couldn't adjust the problem away via the kickdown cable so I took it out to my local auto bloke this morning. He took it for a drive and has suggersted that I have some serious problems with the reco box, but he won't know jsut what until he gets it onto the hoist and has a look. He says it is not a simple fix like the kickdown cable - he adjusted that while I was there - to no avail. At the moment I drive it in selected 2nd at anything under 60kph so as to avoid the constant harsh back and forth cfhanging between 2nd and top.

I'd appreciate any info that anyone might have about the GM180 box and the problem I am currently experiencing.

Regards,
PaulB

Paul, check your vacuum connection between the plenum and the modulator valve on the rear of the GM180 transmission.

Either it has become disconnected or

One of the rubber elbows is split or

The metal pipe is crushed or breached or

* The modulator valve itself, has a broken membrane or

* The modulator valve innards and and seals are shot.

* The latter two assume they transferred your old modulator valve at changeover.

piccy here but not description yet.

Only registered users can see links on this forum! Register or Login on forum!

Alternatively - the kickdown valve has been incorrectly seated or

Is not secured properly by it retaining bracket.

Alternatively - they under-filled the box with ATF without testing the levels as described in the workshop manual, so the fluid level is insufficient to fill the torque converter AND run all the internal valves.

Hi Ramon,
thanks for your response. I will check it and see if I can spot any of the vacuum type problems you refer to. If I can't find anything, I'll give a copy of your comments to the auto transmission guy when I take the car out next Monday (earliest I could book it in).

Regards,
Paul

Hi Ramon,
an update on my malfunctioning reconditioned gearbox. My local auto transmission shop has had a look at it and said that the cause of my problems was a cracked "accumulator". He says the accumulator is made of plastic and needs to be given close inspection to determine its condition. He said he could understand how the other recon shop missed spotting the problem. The bottom end of the gearbox was black when the pan was dropped and my shop advises that one or more of the clutches have probably been chewed up. He will be able to confirm the situation when he gets the box out of the car tomorrow. The good thing is that the other repairer (who reconditioned the box only 600ks ago) has undertaken to pay for this second fix.
Time will tell.
I'd appreciate any comment you might have re the accumulator.
Regards,
Paulcnb

Hello Paul, never heard of a transmission accumulator until now. Googled it and found this

Only registered users can see links on this forum! Register or Login on forum!

Page 17

also some stuff here

Only registered users can see links on this forum! Register or Login on forum!

My son tells me its a simple replaceable item.

Hi Ramon,
thanks for your reply. I had never heard of an accumulator either, thus my question to you. Here's hoping the box is A1 when I get the car back!

P.S. Your son sounds like he knows GM180s pretty well.

Regards, Paul

Hi Ramon,
I for one am glad that your son introduced you to SD1s, because you are a valuable source of information on the marque.

Keep up the good work.

Regards,
Paul.