Forums > THE GLOBAL VILLAGE > The LAND ROVER Forum > MTF 94 disapointment

Mtf 94 Disapointment
Diff

Posts: 1299

 
I changed the oil in my 106,000 mile LT77 gearbox the otherday. it was due for a change, so I thought I would try the MTF94 which is so recommended on this and various other forums. I bought 5 litres from the Landrover main dealer for £20.20. I had hoped that the slightly notchy gearchange, particularly 1st to 2nd, would be improved as a bonus. Not only is the gearchange(particularly cold) no better, it is actually worse than with the ATF oil that I drained out!
Diff

Posts: 1299

 
Although it's suitable for all manual boxes I think Land Rover actually only recommend it for the R380.
Look on the bright side, it may feel worse but it'll last 72000 miles!

Brett
Diff

Posts: 1299

 
Hi Brett, I realise it was brought in to improve the R380 gearchange, but forum feedback I have read included positive reviews by owners with LT77 gearboxes too. Nevermind.
darthdicky

Posts: 2880

 
I'm not sure what's in my gearbox as it was done at the last service (hopefully the next service will be done by me though!), and maybe I've just got used to it after a while (might change my mind after driving my mums little car next week) but it seems so much better than it used to. I always had to fight it from 1st to 2nd and wait a while for it to slot in, but it goes perfectly well now, as does 2nd to 3rd as long as you don't rush it.

Treated gently its a pleasure to use

Very strange...

Richard

Edited to add: I guess it might take a while for the oil to take effect, as all the moving bits will probably still be coated with some of the old stuff that didn't drain out? Give it a few hundred miles and it might well improve?
Ben Reedy

Posts: 2962

 
Sorry to read about your disappointment, I was one who recommended MTF 94. It has certainly made our LT77 a lot smoother to change and a lot quieter when very hot.
Ben Reedy

Posts: 2962

 
Hi all,

Firstly can I say that this is my first post over here and I am from Difflock.com and I have a vested interest in promoting our own range of oils and lubricants but I hope you'll forgive me mentioning my own commercial interests in return for some information I hope will be of use.

I am surprised that you didn't notice some improvement with MTF94 although I believe there is a far better alternative to this particular lubricant (our own Fully Synthetic MT75 Gear Oil).

Nonetheless even MTF94 oil should produce some results almost straight away but in your case there was no improvement.

Did you drain all the old oil out? Typically it takes 2.5 - 2.7 Litres to refill the LT77 & R380 boxes.

Did you remove, examine and clean the plastic filter above the extension case drainplug? (R380 boxes do not have this filter) These filters can twist up and clog with steel swarf and particulates.

Is the clutch in good condition? A failing hydraulic circuit or worn release arm are not unknown at the mileages you have covered.

I suspect one or more of these factors may be contributing to your problem.

To pick up another point, it's true that Fully Synthetic Gear Oils last 2 - 3 times longer than their Mineral counterparts but I would only advise a doubling of the drain interval (to 48,000 miles) to be on the safe side, especially if the box is very heavily worked.

Equally if the oil is contaminated by water ingress then it must be drained and replaced straight away regardless of its base stock (synthetic or mineral) so check it after any deep wading.

As I said earlier, if you want a Fully Synthetic Oil which will truly transform your LT77 or R380 box you should switch to our own Fully Synthetic MT75 Gear Oil. Hopefully someone who is already using it will post their comments here since we welcome independent feedback (you can also read customer comments at the bottom of the store page).

If you would also like a free and detailed guide to renewing the gear oils in LT77, R380 and LT230 (transfer) boxes then send an email to info@difflock.com.

Best Regards

Peter

www.difflock.com
jwriyadh

Posts: 786

 
Peter, I have read the letters from satisfied MT75 users and remain sceptical. I think you are trying to overcome design defeciencies with a lubricant.
However, I am willing to try anything, so can you advise of any distributor for your products (that actually have them in stock!) for the Middle East, Riyadh and Dubai would be good locations.

Regards,
jwriyadh

Posts: 786

 
Hi there,

I agree completely that both the LT77 and R380 box have design deficiencies. Equally our MT75 lubricant is indeed, overcoming some of these deficiencies but its not unusual to use a lubricant in this manner. A lubricant is after all, an integrated part of the transmission system and ideally, its properties should be selected to give the best possible results given the mechanical limitations of any transmission.

Equally I understand your healthy scepticism in this day and age of exaggerated marketing claims. All I can say is that the comments posted on our site, the Difflock Forum and the LRO forum are from genuine customers who have used MT75 and have provided the feedback, unsolicited from us.

Equally, we did a great deal of research before selecting our lubricant range, including visiting the blending plant and laboratories of our supplier.

You can buy MT75 from our online store and we ship worldwide including the Middle East.

Here's some more useful background on Transmission Lubricants which may help explain why synthetic lubricants (of the correct viscosity) are far superior to their plain mineral counterparts and why our very low viscosity MT75 fully synthetic oil produces such excellent results in LT77 and R380 boxes.

Transmission oils have two main functions:

The first function is to minimise friction and hence wear.

They do this by the nature of the base stock (the actual oil) itself which is naturally 'slippy' but also by the use of extreme pressure (EP) additives which chemically bond to the metal surfaces when the metal to metal contact produces high temperatures due to friction. This layer of EP chemicals acts as a sacrificial agent which shears down preventing potential welding of the metal surfaces in contact with each other (another reason why Gear Oils should be changed at the vehicle manufacturer's recommended intervals)

Such Oils are normally rated as either API GL4 or GL5.

In Simple terms, GL4 contains a certain concentration of EP additive, whereas GL5 oils contain twice the amount.

API GL4 oils are used where moderate loads are experienced - Typically certain manual transmissions.
API GL5 oils are used where high loads and speeds are encountered – Typically differentials, final drives etc.

Interestingly, some applications give rise to difficulties with EP additive oils. A notable example is the 4 speed manual Range Rover Gearbox where (with a standard tune engine) the gear loading is not severe enough to require the levels of EP additives found in GL4 or GL5 oils. Here then an engine oil is recommended and used instead.

If you own an older generation vehicle such as a Series Land Rover you must be VERY careful about selecting your transmission oil. This is because certain Extreme Pressure additives containing Molybdenum compounds can give rise to copper leaching and so these will attack the soft metals, such as brass, found in Series Transmissions.

As far as metallic leaching is concerned, whether an oil is GL-4 or GL-5 is only relevant in that GL5 typically contains twice the concentration of additives as GL4. Hence IF a GL5 oil contains the problem Molybdenum compounds then the leaching action will be faster. However both GL-4 and GL-5 oils can be formulated without the problem compounds so the GL rating is not strictly relevant. Note though that the mineral or synthetic base stocks (the oil itself) of a lubricant will not attack soft metals so it does not follow that Synthetic Gear Oils are bad for older transmissions.

Only the lubricant manufacturer (and hopefully your supplier so ask them!) will know whether the problem Extreme Pressure Additive compounds are used and if these are in sufficient concentration to be problematic in certain transmissions.

The second function of transmission oils is to disperse heat.

Special additives are incorporated to prevent highly localised build up of heat within the gear oil. Without this the oil would rapidly oxidise (and lighter fractions in the blend evaporate) gradually increasing the viscosity of the oil and leading to sludge.

Equally the oil has to be of a low enough viscosity to flow around the gearbox in sufficient quantities to disperse heat build up.

Now lets return to the original question of why Land Rover 5 speed boxes require a low viscosity oil.

As with most lubricants, the viscosity is a critical factor in the lubricants performance:

Too thin and the oil film will be insufficient to prevent metal to metal contact.

Too thick and the lubricant will slow down the gearing mechanism (leading to poor and notchy gearchanges) and not disperse the heat generated quickly enough.

Those of you with a Land Rover 5 speed box will know that the gear changes are not slick, especially when the oil within is cold (and at its thickest). So Land Rover has opted for a thin 5W/20 ATF type fluid in order both to improve the action of the synchromesh and provide for good heat dispersal, but with the penalty of poorer metal to metal lubrication.

Now lets consider the benefits of Synthetic Gear oils as opposed to their plain mineral counterparts:

Highly advanced Fully Synthetic technologies will:

1. Eliminate notchy, slow and hesitant gear changes, especially from cold
2. Improve fuel economy
3. Reduce gearbox wear
4. Reduce whine and transmission noise
5. Lower transmission temperature

Fully Synthetic Gear Oils also last up to three times longer than mineral oils before an oil change is required.

Just what makes Synthetic lubricants so superior?

Well unlike ordinary mineral oils such as ATF, EP80 and EP90, Fully Synthetic Gear Oils are far less susceptible to either selective evaporation at high running temperatures, or viscosity variations due to changing ambient or working temperatures (especially on those cold winter mornings). Hence they better maintain an optimum, stable viscosity and have improved flow characteristics at all temperatures.

They have a higher film strength too, which means they are less easily squeezed out of extreme pressure contact areas found on gears and in bearings.

These benefits actually reduce transmission temperature and improve economy since frictional losses become lower. Lower friction also means less noise and so Synthetic Gear Oils are excellent at reducing gear whine and bearing noise.

Synthetic oils are also less prone to aeration (foaming) and this means the lubricant stays more concentrated and evenly distributed throughout drivetrain components.

So those who have switched to Fully Synthetic Oils in your LT77 or R380 5 speed manual gearboxes are indeed very wise to do so. However, by choosing a less than optimum viscosity such as 75W/90 you will not be gaining the full benefits from such oils, namely dramatically improved gearchanges, better heat dispersion and improved economy (typically 3% if synthetics are used throughout the drive train).

Fully Synthetic 75W/90 is of course, excellent for use in transfer boxes and axles on Land Rover vehicles where operating conditions and lubricant requirements are different to those of the main gearbox and a thicker viscosity is specified. (Note the Range Rover Borg Warner Transfer Box requires a 5W/20 viscosity oil).

However, for the main 5 speed gearbox you should be using a Fully Synthetic 5W/20 viscosity gear oil such as our MT75 for best results.

You can find the entire range of both Synthetic and Non Synthetic gear oils mentioned above (including oils compatible with older transmissions and 5W/20 Fully Synthetic MT75 Gear Oil) for sale in the Difflock.com store.

Please feel free to contact me directly if you would like any specific advice on Lubricants and Lubricant Selection.

Best Regards

Peter

www.difflock.com



Diff

Posts: 1299

 
Peter - Yes, ALL old oil was drained, yes, filter was removed and inspected/cleaned. There were no particles in filter, minimum of metal particles on magnetic drain plug, old ATF was fairly clean. My clutch works fine and does not drag or slip, and is correctly adjusted. I believe you miss read my post, the gearchange with MTF 94 is WORSE. It is not a case that I have simply seen no improvement. I changed the oil because it was due a change, not specifically because the gearchange was poor. Having changed the oil, the gearchange is worse. I have considered your MT75, BUT from what you have said above, if I should have seen an improvement with MTF 94, you can appreciate that I am reluctant to speculatively spend more money on the MT 75 that you sell.
Regards,
Diff

Posts: 1299

 
MT75 is a Ford specification gearbox oil is it not? Available cheaply from their dealers even!

IN synthetics, the "Red Line" range of lubricants is a favourite amongst other car groups I'm on; certainly helps stop Rover PG1s falling apart if you try and shove 300 horses through them when compared to the "refill" specified MTF94 or "topup" specified 10W40 engine oil.

"Only the lubricant manufacturer (and hopefully your supplier so ask them!) will know whether the problem Extreme Pressure Additive compounds are used and if these are in sufficient concentration to be problematic in certain transmissions."

For reference, local farming supplies shop deals in "Morris Oils" and have never had problems with the GL5 EP90 in LRs, 'tis whats in my S3 diffs/tx case/OD/box and on the floor, LOL!
Diff

Posts: 1299

 
Yes, MT75 oils were developed for Ford's MT75 and MTX75 gearboxes. The MT75 gearboxes were fitted to SIERRAS(amongst others)in both 4x2 and 4x4 form and the MTX75 is a front wheel drive box fitted to later ESCORTS etc.
Comma also make an MT75 oil.
Diff

Posts: 1299

 
Hi,

Be careful about comparing oils without refering to their detailed specifications guys.

There are other oils called MT75 available and yes these were developed for use by Ford. However, Ford's MT75 specification does not call for synthetic base stocks in the oil and therefore oil such as Comma's MT75 (and I suspect "Cheaply available" other versions) is certainly NOT Fully Synthetic.

As per my earlier post, Fully Synthetic base stocks such as found in our MT75 oil (which is formulated ENTIRELY from Fully Synthetic base stocks) produce far superior lubrication to their plain mineral counterparts when the viscosity is also correctly specified.

This is especially true where the oil's viscosity needs to be thin, such as in LT77 and R380 boxes.

Best Regards

Peter

Diff

Posts: 1299

 
Hi Diff,

Yes I fully understand your reluctance having been disappointed with MTF94.

I have sent you a PM you may like to consider.

Best Regards

Peter
Red90rover

Posts: 3030

 
People might want to try Redline MTL. From the low viscosity MTFs that I have found, it has the best viscosity numbers.

http://members.shaw.ca/jbarge/MTF.htm
northerndefender

Posts: 474

 
I just put in Redline MTL and the gearbox shifts soooooo much easier.  Should have done it a long time ago.
Red90rover

Posts: 3030

 
Colin wins the "bring the post back from the dead" daily contest.  Arrow

Do you know what was in the box before?
dolgarrog

Posts: 381

 
Hope we dont have to wait 7 years for the answer Arrow
Landy Andy

Posts: 1729

 
Put Difflock oil in  Arrow,

One of the best things I have ever done to my 90  Arrow Arrow

Andy
JWL

Posts: 1223

 
It's expensive though. Whilst it may be good stuff, surely it's ruined if you go for a dip?
Landy Andy

Posts: 1729

 
Not if all else is in good order, and extended breathers. Just got my delivery of my next lot as am preping for a big trip  Arrow Arrow Arrow Arrow

Andy
Mtf 94 Disapointment
Jump to forum: Go
Subscription Available

All forums are moderated and should not be used to promote businesses or products. Please create your own profile or group for this. We reserve the right to remove any comment we feel is inappropriate at any time.

Privacy | Terms & Conditions | Subscriptions
MEMBER LOGIN
Connect
Cars For Sale
Featured Advertisers
Members Online
Company Website | Media Information | Contact Us | Privacy notice | Subs Info
Our Other Websites: Auto Express | Computer Buyer | Computer Shopper | Custom PC | Den of Geek | Den of Wii | Fortean Times | IT Pro
London is Free | MacUser | Men's Fitness | Micro Mart | Octane | PC Pro | The First Post | iGizmo
iMotor | DigitalSLR photography | bit-tech