Sticky Manual Gearbox issues in Defender.

[disconut]

When I first purchased the yellow beastie the gearbox was a shocker. Particularly after reversing and trying to get first gear again.
I have changed both the reduction box and main gearbox oils to Castrol Syntrax 75W90 with Slick 50 additive in each. This has made a difference with smoother gear changes, particuarly in cold mornings, and it has also reduced the "whine" to a much lower level. I have now done 25,000 klms since and everthing is good.
Trev.

[Rosco]

Maybe I've missed something here .... but isn't this a new vehicle???

Is so, why in the Kingdom of Cats are you playing around with different oils??

Back to the stealer and raise your voice my lad :twisted: :twisted:
Cheers

[DEFENDERZOOK]

Originally posted by Rosco
Maybe I've missed something here .... but isn't this a new vehicle???

Is so, why in the Kingdom of Cats are you playing around with different oils??

Back to the stealer and raise your voice my lad :twisted: :twisted:
Cheers



how have your gear changes been....?

mine is pretty rough...it will be going back soon....

[Rosco]

Originally posted by DEFENDERZOOK+--><div class='quotetop'>QUOTE(DEFENDERZOOK)</div><div class='quotemain'><!--QuoteBegin-Rosco
Maybe I've missed something here .... but isn't this a new vehicle???

Is so, why in the Kingdom of Cats are you playing around with different oils??

Back to the stealer and raise your voice my lad :twisted: :twisted:
Cheers



how have your gear changes been....?

mine is pretty rough...it will be going back soon....[/b][/quote]


I've not had any problems at all. Tho I do tend to treat it as a truck type gear box and pause thru N .. tho I guess this is pretty well standard procedure ... :roll: :roll:

[DEFENDERZOOK]

you shouldnt need to....it is a synchro box.....i sometimes double shuffle but i shouldnt.....it appears they all seem to do it......

[disconut]

The dealer offered to change the entire thing out for me. I opted to go with synthetic oils and see what happened. The whine was the thing I hated most. I change gears by the double declutch method when towing, just old fashioned I guess. A local chap has just bought a second hand 110 Defender with 80 k on it. He was enquiring about the gear changes being a bit difficult, so I gave him a drive of mine. Last word was he was off to the oil shop.
I also run synthetic in the engine. Castrol R 5W30. I supply it and the dealer changes it for me.
The sales guy drove it also as he had a customer who did not like the gear changes in his. His comment was " can't fault that". There is an option to fit the "Q" gear set to kill the whine.($800 approx plus fitting). This is the Disco gear set, but it changes the ratios.
Trev.

[Rosco]

Originally posted by DEFENDERZOOK
you shouldnt need to....it is a synchro box.....i sometimes double shuffle but i shouldnt.....it appears they all seem to do it......

Been cogitating over it for a mo .. With the previous V8 Disco I occasionally , usually in a fit of immature intemperance tried to emulate Dicky Johnson or Juan Fangio in my gear changing 8) 8) 8) 8)

Upon reflection .. my style in the preceding Defender and pre-preceding County were more akin to my current laid back ... give it time style.

Obviously there must be some significant differences in the boxes, as it would be most imprudent to try racing style gear changes in the Fender.. :oops: :oops: :oops: :oops:

[disconut]

http://www.ashcroft-transmissions.co.uk/part_40.html
Trev.

[Rosco]

Originally posted by disconut
http://www.ashcroft-transmissions.co.uk/part_40.html
Trev.

Now that's interesting style_emoticons/<#EMO_DIR#>/smile.gif style_emoticons/<#EMO_DIR#>/smile.gif

[Captain_Rightfoot]

Mine isn't great either... I thought it was just running in. style_emoticons/<#EMO_DIR#>/ohmy.gif It has got better since we picked it up style_emoticons/<#EMO_DIR#>/smile.gif

[DEFENDERZOOK]

thats the excuse i got......its now two years and 50 000kms later.....

it aint gotten any better......i think its getting worse....

[Captain_Rightfoot]

Originally posted by DEFENDERZOOK
thats the excuse i got......its now two years and 50 000kms later.....

it aint gotten any better......i think its getting worse....

Hmmm... sounds like this might be number 1 on the list. style_emoticons/<#EMO_DIR#>/sad.gif

[DEFENDERZOOK]

i might try a different oil in the morning......see how i feel when i get up....

[disconut]

Link to Castrol Aust and data sheet.

http://www.castrol.com/castrol/multiplepro...ntentId=7000384 (http://www.castrol.com/castrol/multipleproductsection.do?categoryId=8000016&contentId=7000384)

Check out the Castrol R 5W30 spec. Its recommended for TD5 Disco and Defender. :!:

Trev.

[rick130]

Syntrax is the wrong oil for an R380 gearbox (although an excellent choice for the t/case). Its too heavy/thick and Slick 50 is just snake oil. Syntrans TDS is <span style="color:red">here (http://www.castrol.com/liveassets/bp_internet/castrol/castrol_australia/STAGING/local_assets/downloads/s/Syntrans_B13127.pdf)</span>.
Sorry, but if you are going to play around with fluids, use the right viscosities :wink:
The gearbox has an oil pump and lubrication to all the races etc is through internal drillings. The original specifaction fluid was ATF (now obsolete) which are in the 6-7 cSt range @ 100*C. Your Syntrax is over 14 cST @ 100*C, and the current factory fill MTF 94 is @ 10cSt @ 100*C.
I wouldn't use anything heavier than Castrols excellent Syntrans (note the difference in spelling), and make sure it's Syntrans, and not Syntrans M, which again, is way too thick.

As for Slick 50, why use something that contains PTFE, a very slippery substance and friction modifier that is in a basic mineral carrier oil in a very well formulated full synthetic PAO/Ester fluid that already has the correct coefficient of friction for synchros ? Now I reallise some fluids work better than others in certain applications, but the modern MT fluids are awsome.

Sorry, I'm going to climb on my soapbox here, but why do people continually think they can produce oils better than some of the smartest tribologists/oil engineers in the world who have access to the latest and best base fluids and additives by adding an additive that has continually been shown to be a triumph of marketing over substance, and in some cases been extremely detrimental ??

Dump the gearbox fluid and refill with Syntrans. Cold shifting should be better. Most that run Syntrans are extremely happy with it. It is also Castrol Oz's prime recommendation for the R380.
A 75W-90 fluid will also void any potential warranty claim.
BTW, the factory fill (MTF94) is a semi-synth fluid, as is the 75W-90 in the t/case. (both made by Texaco in th UK)

[disconut]

I looked at both and decided to use a common oil. Both were suitable for manual gear boxes. Castrols specs say that this oil is OK for gearboxes with 75W80 oil requirements.
So far all is good. Next change I will give syntrans a go. On the Slick 50 side of things, I have used it for over 25 years in road and race motorcycles, and all of my cars and fourby's. No ill effects I know of. But, I have not kept a vehicle for over 6 years either.
Their marketing is good, as is some of the customer feedback.
My gearbox temps have dropped and the cabin is cooler, especially when towing, so apart from your recommendation for a lower viscosity, apparently it works.

Thanks for the feedback.
Trev.

[rick130]

a list of low viscosity manual trans fluids can be found here (http://members.shaw.ca/jbarge/MTF.htm)

[rick130]

<div class='quotetop'>QUOTE</div><div class='quotemain'>I have used it for over 25 years in road and race motorcycles,[/b][/quote]

did you ever use it in a gearbox with a wet clutch ?
Not trying to be smart, just curious.

[disconut]

For those who might like to read about MTF,This is the not so easy to find spec sheet.. Caltex is the agent.

http://www.caltex.com.au/products_oil_deta...tail.asp?id=107 (http://www.caltex.com.au/products_oil_detail.asp?id=107)

Cheers.

[disconut]

Hi Rick,
Yes, all of the bikes I raced had wet clutches and it dit not worry them. I am not sure why this is so. Maybe the additive cannot "stick", (bad word), to the friction plate material.
Do you remember Roger Freeth the Rally car guy who raced with Possum Bourne for Subaru? He was a motorcycle ace way back and raced at Bathurst etc. He was sponsored by Slick 50 and used it extensively. ( He had a Suzuki 1100 and with an optional 1300 cc engine). I knew him and got into the stuff back then. (1972 roughly). Only wish I could say I raced with him but he was too quick for me. I have used in Honda 6 cyl CBX, CB110R, 350cc trail bikes etc. No issues.

Trev.

[shaunp]

I agree with Rick I think you will find the R380 will change better with Syntrans particularly on a winters morning on top of the Range

[rick130]

Interesting re the clutches, Trev.
Teflon, as used on frypans, etc, apparently requires quite a bit of heat and pressure to make it stay there. (far more than is ever experienced in any engine)
This is part of the claims against Slick 50 and Nulon, et al, that the PTFE they use is a solid suspended in a carrier (mineral oil), and therefore cannot work as claimed. DuPont, the inventors/makers of PTFE are pretty adamant about this. In fact there have been cases of it agglomerating and plugging oil filters in cars.
I used to use the stuff years ago, but when I was racing (cars) I was product sponsored with my oil and was warned off using anything in it. The stuff I was using was wickedly expensive, and one thing they (Neo) and in fact any oil industry person has told me since was that teflon doesn't work. If it did, they'd use it ! Some of the compounds the oil industry uses these days is pretty trick (and costly).

The additive package used in oils is pretty finely balanced with what the tribologist that blends it feels gives the best compromise (as everything is) in the intended application.

Moly appears to be a much better friction modifier as it plates metallic surfaces which are under pressure/load. Redline use a very high level in their engine oils, and talking and listening to some rival blenders, they feel that this, along with other EP and anti-wear additives, is what tends to make it so good in very highly loaded areas like cams and cam followers. The moly they use is a soluble (expensive) version, not molybdenumdisulphide (MoS2). This plating action is why moly is almost never recommended for wet clutches, although I believe soluble moly can be successfully used as part of the additive package.

I still think Syntrax is way too thick, and I wouldn't be game to use it, (although I use it in the diffs and t/case, as well as the t/case in the Patrol). Just compare the actual viscosities of it, Syntrans, MTF94 and any ATF at 40*C and 100*C, and remember that the gearbox was originally designed to use an ATF. (which isn't that great in a MT, but thats another story :wink: )

[Lionel]

I think the original oil (Texaco MTF94) should be the best for the M380 gearbox. Having done a search on all the similar oils I could think of, this seems to have the best viscosity index.

My gearbox was very crunchy as well, when new, and I also experienced the tendency for it to be hard to select 1st after reversing. It has improved greatly after 10,000k's or so with the original oil still in use.

Castrol Syntrans 75W/85 should be OK. although it is a little higher in viscosity than the MTF94, and a bit more expensive.

I think I will stick to the MTF94, which is available from Caltex outlets, if you want to do your own servicing.

Cheers,

Lionel

[rick130]

viscosity index isn't the be-all of rating a lubricant.
You have to be a little careful at times, as an oil like Syntrans has a lower viscosity index than MTF94 as it doesnt contain any, or very little viscosity index improvers which tend to shear quite rapidly in a gearbox application.
Redline don't use any either.
I've used MTF94, Syntrans, Redline MTL and a brew of MTL and MT90 (to combat too thin oil at +35*C ambients-no oil cooler), and Syntrans had the best up shift charcteristics of them all.

[Lionel]

Fair enough! If you've tried all these oils then you're in a good position to make a judgement.

I might give the Syntrans 75W/85 a try myself at some stage.

Cheers,

Lionel

[shaunp]

The thing with most if not all mineral based oils is that once the Viscosity index improvers shear you are back to the base grade oil so loose your high temp/load protection to some degree and you may also notice gear whine or chatter when hot. Syntrans may be more expensive but offers better protection in the short + long term and is also more stable over longer service intervals so you don't need to change it so often, makes it not as expensive as you may think. You will also find the boxes run cooler.