Reverse Delay

[Willow place]

V70 ,2003,Diesel, Is there anyway to cool the auto box more or is it just the normal thing wth higher mileage, from cold reverse is perfect even whilst left for an hour, but when stopping and then reversing (hot) there is a delay, if I only press the pedal a bit there is a thump,so I just wait for the steering feedback? that tells me reverse is engaged normally, to try and reverse up the drive needs at least 1,000-1,500 revs before any movement, fluid has been changed gradually, now the same colour as the bottle .

[ThomasG]

I don't think there's much more that one can do..
Maybe I'm not a specialist, but my own gearbox taught me few things:

If oil wasn't changed regularly when car was young, the damage is done. Done and no oil changes will get it undone.

The damage will be in pressure control solenoid (SLT1?) Where pin "sticks"

For one hand- early gearboxes had dodgy design of solenoid, allowing metal particles in, and since solenoid is nothing else but (electro)magnet- not necessarily coming out.

Add/combine with (posdibly- I don't know your gearbox' story) worn oil and the whole pressure control gets shot to bits.

Option1- change valve body to upgraded or at least less worn (new?) unit.
Think ££££££ and then £££ and some ££

Option2- fit extra cooling to oil lines. Like for towing. Will cost as well, maybe a bit less than valve body, but I think (no experience- I didn't do it) that it will only delay warming up of oil to "shaky/bumpy" temperatures.

[ThomasG]

On the second thought...
I think I know a workshop that could change the valve body without charging arm and leg.

Difficulty is different:

Small town, surrounded by lakes and forests, typically "sleepy" and boring, par summer when its full of tourists and holidaymakers. Beautiful surroundings, clear water, calm and peace. Quite decent chow, too..

And some 2000 miles from you (Almeria, Spain, yes?).

[oragex]

Does it engage better if you rev the engine around 1500rpm? Sounds like the solenoids don't put enough fluid pressure.

[Georgeandkira]

There are posts of people changing their own solenoids. It's not too complex a task but the valve/solenoid body is said to be around $1,150. Similarly, a worn pump (the other source of reduced pressure and increased engagement time) is a job involving removal and teardown.

Since these are so expensive and that you've gotten the fluid clean I suggest a 10 oz. bottle of LubeGard (red bottle). It smoothed out the transmission in my '02 immensely. You have nothing to lose.

This is a USA Amazon listing.

http://www.amazon.com/Lubegard-60902...s=LubeGard+red

[Willow place]

Thanks for the replies, will try the LubeGard, but I must state the auto box works perfectly even when hot, no lurching just smooth changes up and down, just the reverse is where the delay is, a bit embarrassing when trying to reverse when meeting an oncoming vehicle in a narrow street !

[Georgeandkira]

Here's where our collective ignorance shines through.

The reverse actuation piston (a disc of plastic 3" in diameter) in my '76 Chevrolet Nova (T-200 transmission) cracked and the pump couldn't keep up with its ability to leak. Do our trannies even have such a piston?

The LubeGard is said to be tailored to the needs of todays transmissions. You say yours is shifting OK in D. Is there something in the reverse engagement hardware which, due to infrequent use, is sticking in a manner this "wonder juice" will cure? I couldn't tell you.

Since yours goes into reverse I guess we can rule out anything wrong with the PNP switch. Our AW units are electronically controlled.