automatic gearboxes

[greenfingers]

After reading this thread, some of the symptoms seem strikingly similar to those experienced by me and others I have read about with VW AG5 autoboxes.

The coasting/accelerating thud which I had, felt like the torque converter engaging too harshly, but apparently was an ECU related issue which caused the gearbox valves to misbehave.
I don't know if your Merc autoboxes are electronically controlled, but if so this may be a factor.

On a pressure controlled autobox, I believe that the fluid viscosity has a direct affect on how the control valves work. In this case, contamination from clutch plate wear etc can affect viscosity, lubricating properties, and even cause blockages. This would influence the gear changes, and then go on to cause excessive wear. I reckon that a clean filter and new fluid is top of the list.

 

[television]

After reading this thread, some of the symptoms seem strikingly similar to those experienced by me and others I have read about with VW AG5 autoboxes.

The coasting/accelerating thud which I had, felt like the torque converter engaging too harshly, but apparently was an ECU related issue which caused the gearbox valves to misbehave.
I don't know if your Merc autoboxes are electronically controlled, but if so this may be a factor.

On a pressure controlled autobox, I believe that the fluid viscosity has a direct affect on how the control valves work. In this case, contamination from clutch plate wear etc can affect viscosity, lubricating properties, and even cause blockages. This would influence the gear changes, and then go on to cause excessive wear. I reckon that a clean filter and new fluid is top of the list.

Thats the first thing that I would do at the slightest fault on the box, change the fluid, the old fluid can be sived and any particles seen.

Malcolm

 

[greenfingers]

Jeeees Malcolm, have you really had all those cars? If so, you must be either a bank robber, around a hundred and fifty years old, or they must be family heirlooms! :lol:

 

[television]

Jeeees Malcolm, have you really had all those cars? If so, you must be either a bank robber, around a hundred and fifty years old, or they must be family heirlooms! :lol:

Over 450 in all cant put any more up, very often 10 at the same time. It was easy years ago. back in time i would think nothing of going down to the workshop and slip an engine out over night,pick up all the bits in the morning and pop it back in. There was only the earth lead,1 fuel pipe,rad,2 wires on dynamo, and exhaust. There was so much room under the bonnet that you could sit inside on many of them to work. Would not do it now.

malcolm

 

[tom7035]

(Quote) Alvis TC,TE,TF.Alfa Sud,alfeta,2500sprint.Austin7,40,70,90,110,PR,mini ,cooperS.Bedford TK.Crysler Imperial.CitreonID,DS,CX.FordConsul,Zepher,Zodiac. Humber Hawk,Snipe,Imperial.JagMKI,II,5,7,7M,8,9,10.420G,X K120,140,150,E,S type.MB250C,280TE,300TE,SL320,500.Masserati.Morris 8,1800.Pathfinder.RR,PII,20HP.Rover75,90,105,3500, P4,P5.Sunbeam90,Alpine. Saab9000EX.Triumph850,sprint,2500PI.Standard,1,2,3 .Volvo240,V70R.VW (End Quote)

A very impressive list Malcolm, my last count was only 90-something (one at a time though, till now) but I'm sure I've forgotten a couple along the way! My very first DIY job was replacing the rubber/canvas flexible propshaft joint on an Austin 7 Ruby. Happy days! (What on earth were you doing with a TK Bedford by the way, a milk round, or was it during the Korean campaign?!!!) :-D

 

[television]

(Quote) Alvis TC,TE,TF.Alfa Sud,alfeta,2500sprint.Austin7,40,70,90,110,PR,mini ,cooperS.Bedford TK.Crysler Imperial.CitreonID,DS,CX.FordConsul,Zepher,Zodiac. Humber Hawk,Snipe,Imperial.JagMKI,II,5,7,7M,8,9,10.420G,X K120,140,150,E,S type.MB250C,280TE,300TE,SL320,500.Masserati.Morris 8,1800.Pathfinder.RR,PII,20HP.Rover75,90,105,3500, P4,P5.Sunbeam90,Alpine. Saab9000EX.Triumph850,sprint,2500PI.Standard,1,2,3 .Volvo240,V70R.VW (End Quote)

. Happy days! (What on earth were you doing with a TK Bedford by the way, a milk round, or was it during the Korean campaign?!!!) :-D

It was an Ex council tipper, When I bought a farm house and some land, the whole place was full of heavy metal and zinc. I paid £150 for the lorry,there was a full deisel tank on the farm, I rounded up all of the metal and some more from friends and sold it scrap for £450, then used it for building the house and sold it £250, it was a hard life. that was back in 1967. In fact the man next door bought it as he made horse boxes and the TK was a liked chassis for this, the milage was very low.

Malcolm

 

[eric242340]

transmissions

I e-mailed the MB contracts department and got this very helpful reply:

Nice to hear from you. In answer to your query, yes, the gearbox oil and
the filters should be changed at regular intervals (normally at around
40000K or four years whichever occurs sooner). Therefore you should book
the car in to get this done and it would be covered under the Service Plus
contract.

I'm seriously loving ServicePlus

Im sure you are However MB are contradicting themselves, yet again. Wonder what they will say when a new 722.9 goes wrong. On this weve been told never change the fluid, why? I just dont believe this