Thread: Sticky Manual Gearbox issues in Defender.

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. [img]style_emoticons/<#EMO_DIR#>/sad.gif[/img]

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

Link to Castrol Aust and data sheet.

http://www.castrol.com/castrol/multiplepro...ntentId=7000384

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

Trev.

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</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.

[rant]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 ?? [/rant]

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)

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.

a list of low viscosity manual trans fluids can be found here

<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.

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

Cheers.