Autocommand Gearbox

[cosmagedon]

We've got a Autocommand T7 that's very slow to change direction, very jumpy and occasionally rocks backward and forwards when stationary.

Are these symptoms of the solenoids inside the gearbox sticking/failing? Our first AC tractor so we haven't got anything to compare it with.

 

[norse]

Yes the rocking is a classic symptom of a hydrostat control valve/solenoid,I have a T7.270 that rocks slightly sometimes and I am told this valve will sort it, I bought the 270 earlier in the year as having a transmission fault of rocking when at standstill,I had the accumulator checked and it had popped so fitted a new one, calibrated the transmission and it has been a lot better although not as smooth as my t7040 autocommand .
This is the 270

 

[vantage]

Yes the rocking is a classic symptom of a hydrostat control valve/solenoid,I have a T7.270 that rocks slightly sometimes and I am told this valve will sort it, I bought the 270 earlier in the year as having a transmission fault of rocking when at standstill,I had the accumulator checked and it had popped so fitted a new one, calibrated the transmission and it has been a lot better although not as smooth as my t7040 autocommand .
This is the 270

Still waiting to get ours to be done. Trying a software update first, dealer too busy to do it atm! If it doesn’t work surgery will be required.

 

[cosmagedon]

Yes the rocking is a classic symptom of a hydrostat control valve/solenoid,I have a T7.270 that rocks slightly sometimes and I am told this valve will sort it, I bought the 270 earlier in the year as having a transmission fault of rocking when at standstill,I had the accumulator checked and it had popped so fitted a new one, calibrated the transmission and it has been a lot better although not as smooth as my t7040 autocommand .
This is the 270

That looks similar to what it's doing, does it also make it jumpy and very slow to change direction?
Where is the gearbox accumulator and how much pressure is in it? I will have to check that as it's also gone rough changing gear, you can feel each clutch pack when driving now. I've just checked the suspension and brake accumulators and both have popped

 

[Spanner_Man]

Make sure the accumulator is charged to 12bar and a full transmission H8 is carried out before calibration. Solenoid not usually problem until 3000+hours. I also think that filtering the back end oil every 600 hrs with a 3 micron filter helps increase the longevity of the solenoid.

 

[cosmagedon]

Make sure the accumulator is charged to 12bar and a full transmission H8 is carried out before calibration. Solenoid not usually problem until 3000+hours. I also think that filtering the back end oil every 600 hrs with a 3 micron filter helps increase the longevity of the solenoid.

It's just clocked 3500hrs but it's been like this since we had it at 1200hrs. I will get the accumulator checked tomorrow

 

[Spanner_Man]

SWB or LWB? What age is it? T4A or T4B? There is a setting that can be changed in the TCU by your dealer to allow the hydro solenoid to "float" better and alleviate the problem slightly

 

[cosmagedon]

2015 LWB T7.270, can that be done through the H Menu or only a laptop job?

 

[Spanner_Man]

Dealer laptop only, and has to pass all hydro tests before being reset. Only available on 4b onwards so you would need to fid out what yours is. Could be either at that age

 

[cosmagedon]

It's the same styling as our other T7's that are 4a's, is there any other way to tell other than the styling?

 

[Spanner_Man]

Open the bonnet, if the exhaust pipe goes straight from the turbo to the scr cat then it's 4a. If the exhaust goes to a DOC on top of the engine it's 4b

 

[cosmagedon]

I'm sure it's a 4a in that case but I will check tomorrow when I'm in the workshop again.