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Auto box shift problems up and down the box

Truxx

LE
Find a good local autobox specialist.

Sounds like you have a valve failure in the shift system. the old adage applies "no user servicable parts inside"

PS IIRC it's a Mercedes autobox.
If its a Merc box check the oil level

which you cant do according to merc as there is no dipstick.

except you can buy one ( just a flexi cable) from fleabay for a few quid.

into the little tube thing with the yellow cap ( dont do this if its under warranty as it has a paper seal), pull it out.

if its short of oil, it is short of oil.

if there is oil see if its discoloured. Sniff it. If it is remotely manky or smells a bit you have a band problem

also check any plugs and connections. A poor connection will cause issues. If you can get the gearbox ecu read that will identify any areas of concern.
 
Generally the merc autobox is bomb proof. Usually any faults if and when they appear are trans fluid or filter oh and occasional pilotbush all easily sorted. England fred? Works on mercs.he can advise
 
Generally the merc autobox is bomb proof. Usually any faults if and when they appear are trans fluid or filter oh and occasional pilotbush all easily sorted. England fred? Works on mercs.he can advise
Just to add.
Strange as it seems but check battery condition as it will have an adverse effect on box.
 

OneTenner

LE
Book Reviewer
Coincidentally I had a transmission fluid change to do today (actually two, but the transverse one woudn't be relevant to the OP)
Sump pan dropped down exposing the valve block with old filter fitted
IMG_20200821_115355.jpg


Sump pan with new gasket & level tube fitted - also clean the magnet top right in the picture
IMG_20200821_115729.jpg


New Filter....
IMG_20200821_115338.jpg


...fitted
IMG_20200821_115737.jpg


Don't forget the new aluminium bolts & TC drain plug
IMG_20200821_115830.jpg


Bolts are tightened to 4Nm, then 90 degrees, then 90 degrees.
Sorry there are no more photo's but it's a shitty, messy job - in case I'd not mentioned it before!
 

Chicken

Old-Salt
I have a feeling that you have two very separate problems.

Problem 1) Engine cutting out.


Problem 2) Your auto box is fuxxed.I drove two Dodge Rams in the states and the second one needed the trans replaced after doing just the same as yours has.

I have owned 5 American pick-ups over the last 17 years and still own two.I do all my own maintenance and cannot see how the gearbox can turn off the engine,there is simply nothing to my knowledge that can do that on a autotrans in a pickup.

Take it to an independent transmission specialist,they will diagnose it quickly and swap out the trans if needed .
 

Truxx

LE
I have a feeling that you have two very separate problems.

Problem 1) Engine cutting out.


Problem 2) Your auto box is fuxxed.I drove two Dodge Rams in the states and the second one needed the trans replaced after doing just the same as yours has.

I have owned 5 American pick-ups over the last 17 years and still own two.I do all my own maintenance and cannot see how the gearbox can turn off the engine,there is simply nothing to my knowledge that can do that on a autotrans in a pickup.

Take it to an independent transmission specialist,they will diagnose it quickly and swap out the trans if needed .
One of the things that is "transmission" that can stop the engine is a fault in the selector set up. If the selector mechanism /set up thinks you are in "park" it can cut the fuel. Not sure about if it thinks you are in "neutral"
 

muscat_diver

War Hero
Thank you for all of the replies. About 6 months ago I had a problem in the desert sand when powering up a hill in relatively soft sand and had a burning smell accompanied by a loss of power. I stopped almost immediately and let the car cool down. After cooling down I continued slowly with no problems and then went home. The week after I took the car to a reputable Jeep off road garage and asked them to change ATF and filter. Since then it has been fine even when towing boat etc. However just recently I have had this problem so will take it back and tell them the issue and see what they advise - from advice received from the forum I will ask them to change ATF and filter again and analyse fluid see if it is burnt. I changed battery about 6 weeks ago. Batteries only last two years in the Middle East heat. Thank you for all the help and advice, much appreciated.
 

OneTenner

LE
Book Reviewer
Thank you for all of the replies. About 6 months ago I had a problem in the desert sand when powering up a hill in relatively soft sand and had a burning smell accompanied by a loss of power. I stopped almost immediately and let the car cool down. After cooling down I continued slowly with no problems and then went home. The week after I took the car to a reputable Jeep off road garage and asked them to change ATF and filter. Since then it has been fine even when towing boat etc. However just recently I have had this problem so will take it back and tell them the issue and see what they advise - from advice received from the forum I will ask them to change ATF and filter again and analyse fluid see if it is burnt. I changed battery about 6 weeks ago. Batteries only last two years in the Middle East heat. Thank you for all the help and advice, much appreciated.
In that case, i'd suggest a Glycol check to make sure there is no coolant in the ATF, which may be the issue if the ATF & filter was only changed a few months ago (and assuming they drained the TC) presence of Glycol indicates an issue with the tranmission oil cooler.
Also check they are putting the correct ATF in - it's not all the same, whatever the aftermarket parts peddlars tell you
 

Gout Man

LE
Book Reviewer
Have you tried putting some sand in it?*
It will help the bearings to stop slipping and give some grip to the out put drive shaft.:scratch:












*a very cheap and effective way of completely fecking it up.
 

OneTenner

LE
Book Reviewer
Have you tried putting some sand in it?*
It will help the bearings to stop slipping and give some grip to the out put drive shaft.:scratch:












*a very cheap and effective way of completely fecking it up.
Used to be an old pair of tights cut up and stuffed in Cortina rear diffs back in the day, made it quiet enough to sell!
 

Chicken

Old-Salt
One of the things that is "transmission" that can stop the engine is a fault in the selector set up. If the selector mechanism /set up thinks you are in "park" it can cut the fuel. Not sure about if it thinks you are in "neutral"

Not on any yank wagon I have ever worked on it won't.

The selector lever connects to what is effectively a switch with multiple contacts.It has feck all to do with the ECU.The only external interfaces are the ignition lock and the park "sprag".

The trans can't cut out the ignition.It would be a fecking litigation nightmare.
 

Chicken

Old-Salt
In that case, i'd suggest a Glycol check to make sure there is no coolant in the ATF, which may be the issue if the ATF & filter was only changed a few months ago (and assuming they drained the TC) presence of Glycol indicates an issue with the tranmission oil cooler.
Also check they are putting the correct ATF in - it's not all the same, whatever the aftermarket parts peddlars tell you

There would be so much shit under the rad cap Stevie wonder would see it.Thats only if the lines pass through the rad anyhow.

Sound like matey has roasted the trans by towing a heavy boat/ slogging about in the sand.
Heat is an auto boxes worst enemy and it's got to be double nasty when some of that heat is outside the box itself.

I fitted after market trans coolers and braided lines to my current and last Silverado's,my last one has towed 2.5 tons every day over 300k km and is still on the original trans.Thats with yearly fluid and filter changes and allowing the fluid to cool below 70c before turning off the donk.
 

Truxx

LE
Not on any yank wagon I have ever worked on it won't.

The selector lever connects to what is effectively a switch with multiple contacts.It has feck all to do with the ECU.The only external interfaces are the ignition lock and the park "sprag".

The trans can't cut out the ignition.It would be a fecking litigation nightmare.
Sadly not quite the case.
 

OneTenner

LE
Book Reviewer
There would be so much shit under the rad cap Stevie wonder would see it.Thats only if the lines pass through the rad anyhow.
No. The coolant pressure is higher than the circulatory pressure of the transmission oil to the heat exchanger, therefore migration in the event of a leak is only one way - into the transmission. Why do you think that 'Glycol in oil testing kits' are mandated by pretty much every vehicle manufacturer and are the first physical test carried out for 'harsh gearshift concerns'?
I've worked for manufacturers in 'hot places' on development & remediation tasks, all auto 'boxes with electronic control have cooling / torque reduction strategies coded in to the TCM & ECM's, it would be very unusual to have a transmission overheat without some warning on the instrument pack or some form of torque reduction, generally at least two sensors would have to give erroneous readings for this to happen.
 
If as you say this box is a merc box?
Then the symptoms are a defective conductor plate which hold speed sensors which determine gear changes
This plate can be bought as a kit and it comprise of plate ..multipin connector .gasket and filter.
The kit can even be got off Ebay as it's such a common part to be bought.utube will even guide you through fitting it as it's not rocket science.
Some of the suggestions you are getting are over complicating it and quite frankly absurd.
Obviously this only applies if your ATF fluid and filter is in good order in the first place.
 

OneTenner

LE
Book Reviewer
If as you say this box is a merc box?
Then the symptoms are a defective conductor plate which hold speed sensors which determine gear changes
This plate can be bought as a kit and it comprise of plate ..multipin connector .gasket and filter.
The kit can even be got off Ebay as it's such a common part to be bought.utube will even guide you through fitting it as it's not rocket science.
Some of the suggestions you are getting are over complicating it and quite frankly absurd.
Obviously this only applies if your ATF fluid and filter is in good order in the first place.
If that was the case, there would be DTC's - particularly P0715-xx stored, depending on the build region / emissions level, it would also illuminate the EML. A diagnostic check of the control modules should always be the first step.
 
Also check they are putting the correct ATF in - it's not all the same, whatever the aftermarket parts peddlars tell you

Spot on and ever more important in modern engines & gearboxes

Comma website is usually good for correct product, as are Millers and Morris
 
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