VS Auto trans issues

[cattz]

I'm currently in the process of moving house.
Went to tow a trailer the other day and I approached a slight hill.
Whilst going up the hill, the gearbox started to come in and out of lock up.
Pulled it back to 3rd and lock up worked fine.
Drove car yesterday, without load or anything, just had A/C on and gearbox started doing it again.
I noticed the gearbox oil level is a little bit over the full mark and it has a cooler on it.
The box is also out of a VX and is due to be serviced soon.
Oil doesn't smell burnt and is still a red colour.

COULD this be a gearbox issue or maybe even a computer fault?

 

[BlackVXGTS]

Not sure where you are driving (city or country), but either way, 4th is not supposed to be used when towing.

 

[cattz]

Not sure where you are driving (city or country), but either way, 4th is not supposed to be used when towing.

Oh, didn't realise that one, but it still shouldn't be doing it with just the A/C on.
And it was towing on the Freeway/Highway.

 

[TheVsStig]

i have had a similar problem in the past, i went to many trans shops and they all said the 3rd to 4th clutch had burnt out, and i needed a full rebuild (1000-1300). i didn't have much money at the time so i decided to just do a service and see if it helped.

well turned out yes the 3rd to 4th clutch wasnt in the best shape, it had droped a heap of black crap into the pan and hence blocked the filter. i cleaned the pan out and changed the filter, this was no permanent fix but i got about 15000k's before i had to change the tranny.

just saying if your on a budget this would definately be worth a try. and i have heard of this happening quite a few time even from my grandfather back in the 70's with his hq

 

[cattz]

Just an update.

Took car for a drive on Saturday with 5 people in it and it was still doing it up a hill at 110km/h.(In 4th and lock up, just goes in and out of lock up constantly)
Slowed down to about 80km/h pulled it back to 3rd (with lock up in) and worked just fine.
SO could it have a TPS issue or has anyone found something else if they had a similar problem.

PS: Transmission Filter changed about 3000kms ago.

 

[shadetreemechanic]

Could be ya TCC apply valve or solenoid. Its controlled by PWM in the 95 and up model tranny and it loses pressure if worn out. Would cause the lockup to engage disengage....im no expert though so i could be all wrong.

Definitely not an issue with 3-4 clutch as thats usually fatal and wont work at all. This is the weakest link in the 4L60E though. By the way its actually better to select overdrive range for this reason as there is more pressure in the circuit available for the shift since in manual third the overrun clutch is also applied at the same time and saps line pressure from the 3-4 clutch pack.

When towing engage the PWR button as it ups line pressure and changes the shift points accordingly as well as keeping the converter locked up longer. You can actually tow in overdrive range as it will only shift into 4th at 84kmh closed throttle (in PWR mode as opposed to 48kmh with PWR off). Though you will want to hold it in manual third if you notice it dropping in and out of OD or unlocking the converter. And downhill for the engine braking from overrun engage.

Towing regularly, get an auxiliary trans cooler and trans temp gauge.

 

[DJ_Cosmic_Fire]

Took car for a drive on Saturday with 5 people in it and it was still doing it up a hill at 110km/h.(In 4th and lock up, just goes in and out of lock up constantly) Slowed down to about 80km/h pulled it back to 3rd (with lock up in) and worked just fine.

Nothing to worry about from what I read, your PCM (ECU) is in control of the Auto Transmission being Electric, & with 5 people it would have a sense of more weight same as towing etc. Same thing with the earlier TH700 in VN/VP, except they are Hydraulic (operate on line pressures only) except for an electric solenoid which is energised to lock up the engine directly to the drive shift from the ECU (PCM) usually at 75 to 80 km's onwards. Direct drive will change consistently with fluctuating traffic, sudden acceleration & even tapping the brakes with disengage the TLC. To really test if things are ok with your clutch bands, try find a long stretch of highway & when Direct drive is engaged just cruise, don't gas it & don't hit the brakes. If all is not too good, the trans will jump from 3 4 3 4 on a regular basis, & that's time for an exchange unit to be arranged. If all is good on this cruise & there is no need to hit the brakes or gas it - then as above mate, absolutely nothing to worry about.