Mercedes 320 CDI - Auto Box Oil Change - Steveieb
My indie is a little reluctant to change the auto fluid in my 130k mile 320.
He claims it could cause more problems than leaving well alone.
But I understand that there is a filter which needs changing too.
Grateful your views
Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

Ask another MB indy?

Mercedes 320 CDI - Auto Box Oil Change - John F

I would follow your indie's advice. I remember reading an article by a transmission specialist saying exactly that.

Most garages like to do as much work as possible, its magnitude often directly proportional to the credulity of the customer, so by not advising unnecessary work it sounds as though your indie is a good'un.

Mercedes 320 CDI - Auto Box Oil Change - cws

Your indie is either misinformed or can't do it and wants to save face.

What year/number of speeds is the box? 5speed (5G) boxes are on an interval of around 35K. 7speed boxes are split between 7G (also 35K interval as I recall) and 7G+ (stop/start vehicles-70K interval). Sealed for life is utter nonsense and MB has also quietly buried this guidance....

Go to another indie and also ensure they use the correct ATF.

Mercedes 320 CDI - Auto Box Oil Change - Soldrax

I second Cws' point.

It is especially important to change transmission fluid if you tow.

Mercedes 320 CDI - Auto Box Oil Change - Wackyracer

A transmission specialist is probably the best port of call.

Mercedes 320 CDI - Auto Box Oil Change - Metropolis.
I found this video helpful when deciding to change my
auto gearbox oil at 66k. When it comes to auto gearboxes
best place to look is USA.

youtu.be/o690DovjDAc

I changed mine (not flush) and what a difference! Much smoother,
slightly better mpg as it doesn't seem to need to
downshift to accelerate as much as it did before.

I really was in 2 minds about it. I think the major caveat here
is if it has been neglected for too long then it becomes
risky changing it as you'll disturb particles etc that will
block valve bodies. In those circumstances the box
will be short lived anyway so always better to change i think !

There is a federation of auto gearbox specialists, although
my local independent did it &i is very trustworthy.

www.fedauto.co.uk

One other thing, I heard that some Lexus USA
dealerships change auto gearbox oil annually or 20,000
miles! As i said, the americans know automatics
better than we do so i find their practices much mitre
authoritative on the issue.
Mercedes 320 CDI - Auto Box Oil Change - RT

In America, oil and ATF are very cheap - many there still use 3,000 mile oil change intervals.

Personally, I prefer to use colour/smell of the ATF to determine when to change - translucent red is new, opaque red is ok, brown needs changing and black/stinky is too late!

Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

Cheap here too if you avoid paying for glass palaces suits receptionists managers etc.

I have 20 ltres of the correct Dexron6 autobox oil waiting to go into my Landcruiser which cost around £70 delivered, slightly cheaper for good gear oil, and the full synthetic quality engine oils i usually buy for between £15 and £20 per 5 litres due to getting 20/25 litre drums...now all i need is a dry day without a wind howling up the Khyber pass.

Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

Rightyo gents, the weather was kind'ish and i've just got out of the shower having changed all the oils, most of which ended up on me which is fairly normal, also greased the two propshafts.

Gearbox oil @ approx 95k miles was a nice consistency if you can judge such a thing, but it was a dirty light brown instead of the clear crimson it should be, i shall run it for a few months and change it again, its almost impossible to remove all the old oil from the torque converter so for piece of mind i shall run another batch through it when it's done a few miles, i usually change a sumpful annually on cars that have a dipstick/filler tube because it's as easy as changing the engine oil which i usually do at the same time, this one is more fiddly so when it does get done it's worth doing the full job.

I haven't road tested it but it glides into gear now appreciably smoother, and i thought it was smooth before, just want to rest now i'm back on shift early hours tomorrow.

I would be very interested to see the OP's oil after 130k.

Edited by gordonbennet on 09/06/2017 at 16:17

Mercedes 320 CDI - Auto Box Oil Change - John F

....but it was a dirty light brown instead of the clear crimson it should be,....

This below might be of interest from an apparently authoritative site...... I have always had a slight leak from my TR7 gearbox which requires an occasional top-up with crimson ATF. It has not been actually changed in 70,000m and 35 years, and continues to work perfectly. My original BL book says change the engine oil every 6,000m but there is no requirement to renew the ATF or the oil in the final drive - so I haven't. If it works, don't mend it!

The color will change over time as it ages, is subjected to heat and friction, and collects contaminants (dirt and debris). It typically starts out bright, translucent pink/red and slowly transitions to a darker, more brown and more opaque color until it appears black. This process is completely normal and does not mean there is a problem.

Mercedes 320 CDI - Auto Box Oil Change - Wackyracer

I haven't road tested it but it glides into gear now appreciably smoother, and i thought it was smooth before, just want to rest now i'm back on shift early hours tomorrow.

I know my Toyota's autobox changed up and down much smoother after I changed the ATF at 56,000miles. Although I did it a bit heath robinson by pulling the hose off the bottom of the rad and starting it so it pumped the fluid out (this got out much more than draining by the drain plug) then topped up by the same and ran it through the gears a few times before doing it again a couple more times.

Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

I know my Toyota's autobox changed up and down much smoother after I changed the ATF at 56,000miles. Although I did it a bit heath robinson by pulling the hose off the bottom of the rad and starting it so it pumped the fluid out (this got out much more than draining by the drain plug) then topped up by the same and ran it through the gears a few times before doing it again a couple more times.

Only just spotted your post Wackyracer.

Yes i could have drained it that way too but for the LC there are several warnings about only pumping out roughly 4 litres at a time via the flow going through the cooler, then topping up the box and continuing.

Knowing my history with pipes under pressure (and my usual method of dowsing the surroundings in oil spray), i decided that instead i would drain a sumpfull, refill then run for 10 mins or so going through all the gears, then repeat, which i did several times, each drain the oil clearing a little, your method is better without a doubt but maybe not for me or my drive :-)

As far as i'm aware, if Steveieb has the 7 speed box on his steed, then changing the oil is a very specialised operation, the oil apparently has to be pumped in from beneath with the Merc STAR system linked up controlling the operation, if he does get the oil changed i hope he gets the garage to save a sample for his inspection and reports back on any changes to the gearshifts.

Mercedes 320 CDI - Auto Box Oil Change - John F
One other thing, I heard that some Lexus USA dealerships change auto gearbox oil annually or 20,000 miles! As i said, the americans know automatics better than we do so i find their practices much mitre authoritative on the issue.

Oh yeah? It appears tantamount to fraudulent extortion to me.

Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

attn Steveieb.

drove the L'cruiser today for the first time after changing the gearbox oil.

Goes into drive or reverse smoother, gearchanges are difficult to notice so silklike are they, lock up in top comes in sooner, there was noticeable delay getting lock up at the end of one slip road i use every day that has now disappeared.

One other thing, the thing that urged em to get on and change the oil, when slowing up gently approaching a junction, there was sort of vibration that one could feel through the car now and again, if you had partial clutch engagement in a manual that is the best way i can describe it, that has now disappeared too.

Will definately be changing it again when i'm off for another week next month.

This is the 3rd Japanese 4x4 auto box i've changed the oil on in the last 4 years, every time the difference is noticeable.

Will be dropping and refilling a gearbox sumpful on SWMBO Outback as well when i change the engine oil in the autumn, its as easy as pie on the Scoob because dipstick tube.

Mercedes 320 CDI - Auto Box Oil Change - RT

Will be dropping and refilling a gearbox sumpful on SWMBO Outback as well when i change the engine oil in the autumn, its as easy as pie on the Scoob because dipstick tube.

Don't forget the front & rear diffs and transfer box - one of them shares the ATF but it's so long ago I can't remember which.

Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

I changed all the transmission oils on the Scoob 3 years ago RT so the diffs and transfer box should be fine, second year i dropped a sumpful of autobox oil and replenished but can't recall doing so last (own wrist slapped) so this year is a must.

I only wish Toyota hadn't joined the herd by dumping the gearbox dipstick around 2003, thankfully the Scoob still has three dipsticks under the bonnet..and yes i know the reply to that one..:-)...and is such a pleasure to work on, well apart from spark plugs.

Mercedes 320 CDI - Auto Box Oil Change - RT

I changed all the transmission oils on the Scoob 3 years ago RT so the diffs and transfer box should be fine, second year i dropped a sumpful of autobox oil and replenished but can't recall doing so last (own wrist slapped) so this year is a must.

I only wish Toyota hadn't joined the herd by dumping the gearbox dipstick around 2003, thankfully the Scoob still has three dipsticks under the bonnet..and yes i know the reply to that one..:-)...and is such a pleasure to work on, well apart from spark plugs.

I miss dipsticks! Not only could you check the fluid level, you could check the fluid colour/condition - after my Outback, my Hyundai had no ATF dipstick but the dealer agreed to report at each servicebased on fluid sample from the fill point - my Touareg has no dipsticks at all so I'm totally reliant on VW electronics, ok till it goes wrong!

Mercedes 320 CDI - Auto Box Oil Change - Steveieb
Thanks for all your contributions. The MB gearbox is allegedly Sealed for life and a MB specialist iwho services all the taxis removes the sump, changes the filter and then fits new bolts. Understand the main dealer spends four hours trying to refill the oil and charges over 400 pounds.

My friend refused to pay and threaten ten to take the Car away with the spare key when they would not release the car
Mercedes 320 CDI - Auto Box Oil Change - John F
Thanks for all your contributions. The MB gearbox is allegedly Sealed for life.

So why on earth do you think that you, or your mechanic - who might proudly have a level 3 NVQ - know better than the cream of the Herr Doktor Professors who design and manufacture such things? I have had autos for over half a million miles and never changed the oil in any of them - as per manufacturer's recommendation. All worked perfectly to well over 100,000m, a Passat to nearly 250,000m.

Mercedes 320 CDI - Auto Box Oil Change - Metropolis.

I appreciate your frugality John, but 'life' was never meant to mean more than 100,000 miles or so, just beyond when they'd expect most to trade in for a newer model and it becomes someone else's problem! Even Mercedes have now backtracked on the 'sealed for life' idea. ZF recommend 60k mile intervals under normal use.

Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

Even Mercedes have now backtracked on the 'sealed for life' idea. ZF recommend 60k mile intervals under normal use.

You're the man to know PCharlton, when i delivered RR's by the hundred till i changed jobs 8 years ago there were labels stuck to the gearbox oil pan re 'sealed for life' or words to that effect, i noticed these labels especially on cars bound for the US market, i doubt US owners or mechanics took too much notice of those stickers mind.

Is SFL still the case with LR gearboxes, or have they gone back to sensible too?

Mercedes 320 CDI - Auto Box Oil Change - Metropolis.

I'm not actually sure about the newer models although I have seen plenty of Discovery 3's going in for a transmission flush. My 2003 TD5 Discovery has it in the service schedule though!

Mercedes 320 CDI - Auto Box Oil Change - John F

I appreciate your frugality John, but 'life' was never meant to mean more than 100,000....................ZF recommend 60k mile intervals under normal use.

NO NO NO! Not for 'normal use' they don't!!! Only for very hard-worked gearboxes. It is very disappointing when people post erroneous information which can persuade the unsuspecting cautious motorist to incur huge unnecessary bills plus the added risk of a difficult job not done properly using the wrong fluid. Below is copied from the ZF website...

5-, 6-, 8- and 9-speed as well as 4HP20 automatic transmissions: ZF 5-, 6-, 8- and 9-speed as well as the ZF 4HP20 automatic transmissions are filled maintenance-free with specially developed partially synthetic ATF oils. Maintenance-free fills are intended for normal operating conditions. Especially driving at very high operating temperatures can result in accelerated aging or increased wear of ATF oils. In case of above-average operating conditions, such as: - frequent freeway driving in the upper speed range - offensive, sporty driving style - frequent trailer operation it is recommended to refresh (change) the oil of the automatic transmission every 100,000 km or no later than after 8 years. In each case, only released ATF oil may be used for oil changes. And oil changes must be performed in accordance with the relevant specifications.

....so for normal drivers, and probably especially for the 'hundreds' of presumably Phantoms that gb delivered (ZF6HP26 - 2 wheel drive version of the one in my Audi), there is absolutely no need to change the fluid - although I suppose they can easily afford it!

Mercedes 320 CDI - Auto Box Oil Change - Avant

I see your point, John, but one could debate what is meant by 'hard-worked gearboxes'. For most mechanical parts of a car, the most challenging type of use is short journeys with the engine and gearbox cold.

It must be an easier life for both engine and transmission to be driven smoothly by a professional like Gordonbennet in his lorry, mostly on M-ways and main roads, than by occasional, un-car-sympathetic motorists like Arthur Punter on his trips to the shops / station etc and his 5,000 miles a year..

Edited by Avant on 12/06/2017 at 16:33

Mercedes 320 CDI - Auto Box Oil Change - Metropolis.

I just checked ZF itself, they recommend the following:

"After an oil change, it is easier to shift the transmission and the service life is significantly increased. Therefore, it is recommended to have one of our Service Centers perform a complete oil change after 80 000 km for passenger cars and approx. 250 000 km for commercial vehicles.

When it comes to an oil change, perfection and efficiency are more important than ever. Therefore, ZF Parts oil change kits are the perfect solution. We provide workshops with everything in a single package, suitable for the respective vehicle type - from bolts to the right transmission oil."

Source: www.zf.com/corporate/en_de/aftermarket/services/re...l

Mercedes 320 CDI - Auto Box Oil Change - John F

I just checked ZF itself, they recommend the following:

Source: www.zf.com/corporate/en_de/aftermarket/services/re...l

That text is contradicted by Page 5 of ZF's maintenance recommendations - dated April 2017 - see link.....

www.zf.com/global/media/en_zf/lubricantslists/TE-M...f

As I have often said, garages (or 'aftermarket servicers') like to suggest as much work as they possibly can. You pays your money and takes your choice....

Mercedes 320 CDI - Auto Box Oil Change - barney100

Get in touch with section captain at the Merc owners club.

Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

I can see JohnF's points, and up to a point if a person was stuck with only main dealer servicing where a gearbox oil change could be knocking on the door of £300, 4 of those changes over say 160 or 200k miles costing some £1200, then yes one might be tempted to risk the box especially when the vehicle gets over half life..

For many of us though where changing the box oil could be half that at an indy or 1/5th by DIYing, then it's almost criminal not to give one of the most expensive parts of the vehicle every chance possible of lasting as long as the vehicle instead of possiby being the reason for scrapping.

Manual boxes no different, most normal cars the oil would cost £30 tops and a couple of hours tops even struggling on the driveway, why on earth would anyone risk a £1000+ box for the sake of £30 every 40k miles, it simply doesn't make sense to me, but then lots of car things don't make sense any more like never checking your engine oil and getting the hump because the engine is seized or damaged costings £hundreds at no mileage to speak of.

I wouldn't mind but the cost of good servicing pales into insignificance in the grand scheme of car ownership.

Mercedes 320 CDI - Auto Box Oil Change - corax

My Foz requires oil changes every 30k miles as part of the service schedule. I think it's a sensible move by Subaru to prolong gearbox life. I'm glad that they have a pride in their engineering that they would want to prolong the mechanicals rather than the short term idea of sealed for life then the scrapheap. Admittedly the car is four wheel drive, and so places extra stress on the gearbox.

I changed the oil for a different 50/50 mix suggested by Subaru forums. Gearbox shift quality was OK before, now it is superbly slick and effortless at all times of year including winter. Reverse on these is non synchromesh, it is now much easier to select.

I'm sure that many manual gearboxes will run for many thousands of miles without an oil change, but if you're keeping the car for a long time, doing so may make gear selection feel better.

Mercedes 320 CDI - Auto Box Oil Change - RT

My Foz requires oil changes every 30k miles as part of the service schedule. I think it's a sensible move by Subaru to prolong gearbox life. I'm glad that they have a pride in their engineering that they would want to prolong the mechanicals rather than the short term idea of sealed for life then the scrapheap. Admittedly the car is four wheel drive, and so places extra stress on the gearbox.

I changed the oil for a different 50/50 mix suggested by Subaru forums. Gearbox shift quality was OK before, now it is superbly slick and effortless at all times of year including winter. Reverse on these is non synchromesh, it is now much easier to select.

I'm sure that many manual gearboxes will run for many thousands of miles without an oil change, but if you're keeping the car for a long time, doing so may make gear selection feel better.

Subaru autoboxes are an anomally - they originate, way back, from a Nissan Jatco gearbox that had a poor replutation for reliability - Subaru developed it independntly enabling excellent torque handling with excellent reliability - but only possible with regular ATF changes that didn't get longer over time/fashion like many others

Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

Just given the box its last flush for this period, oil coming out was much nicer colour than a few weeks ago.

Also changed the engine oil and filter whilst down there and dirty, now featuring Shell Helix running through its veins, and i'm feeling me age.:-)

Subaru gets an engine oil change later in the week, and i'll drop and replenish a 5 litre sumpfull from the autobox while its raised, much easier with that, still has a good old gearbox dipstick.

Mercedes 320 CDI - Auto Box Oil Change - Wackyracer

Just given the box its last flush for this period, oil coming out was much nicer colour than a few weeks ago.

Also changed the engine oil and filter whilst down there and dirty, now featuring Shell Helix running through its veins, and i'm feeling me age.:-)

Subaru gets an engine oil change later in the week, and i'll drop and replenish a 5 litre sumpfull from the autobox while its raised, much easier with that, still has a good old gearbox dipstick.

Good stuff, certainly a nice day to do it. How do you get the ATF back in the box without pouring it down the dipstick tube (which it doesn't have).

Edited by Wackyracer on 02/07/2017 at 17:12

Mercedes 320 CDI - Auto Box Oil Change - gordonbennet

On the Scooby it is a pour down the dipstick tube job, simplicity itself.

Toyota has no dipstick, has two plugs on the bottom of the sump, one drain plug one slightly higher level plug, same as with most autoboxes check the level in P with engine running and in this case gearbox oil at 46/50', there is a trick method where the car tells you by warning lights when the gear oil is the right tempt for level checking.

Toyota has large filler plug semi hidden about 2/3rds up the box, i have a simple and cheap two way hand oil pump which came with about a metre of clear flexi pipe, pump has an in and out pipe fitting at the bottom, so just hand pump the same amount of oil in as was drained out...professionals would probably laugh at this £10 pump but it does the trick...mind you doesn't matter how hard i try i always end up with a decent batch of oil over me, today was one of my better days only maybe one teacupful ended up on me.

Didn't make so much mess draining the engine as usual either, holds 7.5 litres and comes out at a terrific rate (Fumoto do not recommend their excellent drain valves for my sump more's the pity), splashed all over the shop when i used my normal drain can, wonder if SWMBO will work out where her second sink bowl has ended up, can't possibly return it now, it was torquoise before..:-)