X250 Gearbox Oil

[kevina]

Today I changed the gearbox oil in our 2008 130mj 2.3 with 50,000 miles on the clock. It has sometimes been difficult to engage reverse so I thought I'd try this first even though normal driving is slick. We had the reverse gear modification carried out in 2010 so the oil would have been changed then. The correct quantity is supposed to be 2.7 litres but I carefully measured the drained oil at 2.3 litres. I haven't road tested it yet but could this conceivably have accounted for the problem? There was only a small amount of metal filings on the drainplug magnet.

 

Kev

 

 

[Brambles]

You may find lubricating the external parts of the gear change mechanism, especially the shaft where it goes into the gear box cures the problem. You can tell if it needs doing if you select reverse and then pop the gear lever out of reverse but see how well it slides back to its normal rest position by itself (with the engine not running).

[Derek Uzzell]

Kev

 

I’m doubtful that having 2.3litres of oil in the gearbox (instead of 2.7litres) would have negatively influenced how easy it was to select reverse gear.

 

However, I’ve always been wary of the ‘retrofit’ gearbox modifications that were made at Fiat dealerships to address the juddering-in-reverse problems that badly afflicted some early Ducato X250 vehicles. I’ve never been confident that the fine mechanical clearances that would have been taken into account when the gearbox was originally manufactured would always have been replicated during the rebuild.

 

You could try Brambles suggestion and, if selecting reverse is REALLY difficult, you could try using a transmission additive (eg. Molyslip G MTS).

 

The sensible thing though is to drive your motorhome for a while now that it has new oil in the gearbox and see if reverse-gear selection has improved.

 

Selecting reverse-gear on my 2015 Ducato X290 can prove obstructive - in fact gear selection generally is uninspiring. It’s better than it was when the vehicle was new (which is to be expected) but it’s never going to be ‘knife-through-butter’. The Ducato is a ‘van’ and it shows...

 

 

[kevina]

Thanks for the replies, I have lubricated the shaft in the past. The funny thing is that I can select reverse perfectly half a dozen times in succession then the next few times it will be difficult. On a previous thread a few years ago I think Nick (Euroserve) said it could be the clutch (which was also replaced in 2010). One thing I forgot to mention was that after about 45 minutes driving the gearbox/clutch starts to sound a bit rattly so it will be interesting to see if an extra 0.4 litres of oil has cured that.

 

I won't really be able to test it now before we head south in 3 weeks time.

 

Kev

[John52]

Oil works like a skier being towed over water. It only works whilst the skier is moving, as soon as the skier stops he sinks. It works great on a fast turning crankshaft because there is lots of sliding movement, but when gears engage there is very little sliding movement, and enourmous pressure. Gear oil has the hardest job of all and some metal to metal contact is inevitable. To minimise this its designed to cling to metal. You could well have 0.4 litres still clinging inside when you drain it.

[kevina]

I did wonder about this, however it did drain pretty quickly and 0.4 litres seemed like quite a lot of missing oil. I guess then that it may now be slightly overfilled but this is probably preferable to being substantially underfilled.

[John52]

kevina - 2016-09-24 4:36 PM

 

I did wonder about this, however it did drain pretty quickly and 0.4 litres seemed like quite a lot of missing oil. I guess then that it may now be slightly overfilled but this is probably preferable to being substantially underfilled.

 

I wouldn't worry about it. Worst case scenario is 0.4 litres overfill but the gearbox casing is wider higher up so even that isn't going to make a serious difference to the oil level.

[John52]

Mine X250 has the MLGU P. 6 speed gearbox as fitted to the 2.2 and 2.3 (don't know about the 3.0)

When it was new I took out the plastic plug which covers a 3cm hole. Its held in place with a bolt requiring an allen key. I checked the oil level by dipping in the allen key - 15mm below the top. . Just checked it again after 8 years and 62,000 miles to find the level is still the same.

But the plug is very difficult to get at. You can't see it from below, only feel it. Its just above the point where the OS driveshaft exits the vehicle. Probably easier to take the battery box out so you can do it from above. And have a spare plug in case you crack it prising it out. Unless you have reason to think the gearbox has lost oil its probably better left alone as checking the oil level is not a service item.

 

Attached a couple of photos I have just taken - of the plug and the hole.

[John52]

Took the battery box out today. Not much more work than taking out the battery - just 4 bolts and it lifts out. Certainly makes access to the transmission filler plug much easier - so you can check the area around the plug is clean and prise it out evenly to reduce the risk of cracking it - also makes it possible to add oil with ordinary filler bottle.

With my finger I can feel a ledge machined into the casing about where the oil level is and has been from new - about 15mm below the top.

I would not attempt to access this plug from under the van again.

Took a couple of photos from inside the van through the battery box hole

[John52]

X2/50 van was manufactured in 2008. No sign of rust on bodyshell or doors which is galvanised. Some other areas like these battery box straps have rusted heavily. But the battery box looks strong enough to support the battery without them.

[aandncaravan]

John52, a great reply and clearly a lot of work gone into it.

Excellent description and good photos too.

I like this.

 

 

Kevina, If Reverse is hard to select only sometimes that might suggest a sticky Clutch release mechanism?

 

To moderators/developers, is it possible to have a Emooticon which is a 'Big Tick' to show you like a Post?

 

 

 

[John52]

Thanks for the Heads Up :-D

I took the battery box off because I was concerned about the straps rusting through as I could only treat one side from underneath. Having got the box off I can see it looks strong enough without the straps to hold the battery in normal circumstances. I guess the straps are there to hold the battery in the event of a collision.

[La Hobo]

Great pictures, I wish more people would add them to the text, makes the words a lot easier to understand. Thankyou!

[Airstream]

Van now 10 years old so thought might as well change the gearbox oil whilst doing the yearly service 20 mins max and 18 of them waiting for the old oil to drain and refilling the box as very slow to fill

All that is involved remove drain plug, drain oil, refit plug, pull off bresther cap, fill gearbox via breather hole with required amount of oil , push back breather cap, job done

 

Ray

 

 

 

 

 

 

 

 

 

[mikefitz]

Kev, a few things about the MLGU6 gearbox you may find interesting.

 

There is adjustment on the cables under the dash gear lever boot. It is kind of ratchet that adjusts the length of one of the cables to ensure the reverse position clears the interlock correctly.

 

The recommended oil is Tutela Experya SAE 75W-85 GL-4. The GL4 rating is important, other grades can compromise the syncro rings. On the 6 speed gearbox the listed quantity is 2.7 l, however the last new boxes I have fitted are engraved fill 2.9 l.

There is an alternative fully synthetic oil, Tutela Matryx SAE 75W-85 GL-4 that I have used in this box with good results.

 

Some boxes are refilled at 2.4 l, this error exists due to this being the recommended amount for the 5 speed box. There will always be some oil left in the box, but at the most half a cupful.

 

The box design is poor, with in my view, undersized and badly located bearings. At the first sign of gearbox noise and/or excessive movement of the gear lever on the overrun in 6th gear, consider getting it rebuilt .

 

Mike

[Airstream]

I used Redline

Will see how it performs

Ray

[jjsbc]

Here is an interesting thought maybe Fiat calculated residual oil held in the box and 2.7 liters is correct ?

Retired engineer,

P.S.personally if it says,2.7liters I would do it.

[Airstream]

When i refilled my gearbox i put in 2.7l as stated the handbook

[aandncaravan]

jjsbc, Do you mean that the gearbox should be filled with 2.9L when new, but any subsequent oil change takes account of there being oil left in the box, so a 'drain and refill' of 2.7L?

 

If new boxes were incorrectly filled with 2.7L, then that might, possibly, explain why nearer 2.4 litres is being drained at a later date, because 0.2 litre'ish is left behind.

Maybe as a result of confusion at the factory they were filling at 2.7L which might also explain why Fiat now engrave 2.9L fill on new boxes, but list 2.7L as a 'drain and fill' measure?

 

I think if it was me, I would use 2.9L to fill a new box but stick with 2.7L at oil change time.

 

 

It never ceased to amaze me just how poor Gearbox oil looks when drained at around 50,000 miles and if what mikefitz says is true about the bearing locations, it sounds like a good idea to change it at this sort of mileage or 10 years of age, whichever is sooner.

 

 

[Steve928]

aandncaravan - 2018-05-04 10:28 AM

 

I think if it was me, I would use 2.9L to fill a new box but stick with 2.7L at oil change time.

 

 

Although Totale's (Peugeot's oil partner) website lubricant selector has changed and now states only 'Capacity 2.9l' for the MLGU6 box it did previously state just that i.e. '2.7/2.9 refill/capacity' or similar wording.

 

Interestingly Peugeot/Totale use a different grade oil in the MLGU6, namely 75w-80 GL-4. Perhaps Totale don't make a 75w-85 version.