K series 6 speed - gearbox oil recommendations

10 posts / 0 new
Last post
Nick Bassett
Nick Bassett's picture
Offline
Last seen: 5 hours 16 min ago
Joined: 17/04/2014
K series 6 speed - gearbox oil recommendations

Hi folks,

Now that I have my engine back from DVA nicely refreshed, I'm planning on putting this big chunky jigsaw puzzle back together... just hope I'm not missing any parts!

Gearbox oil - what should I be using? I know I've read somewhere about Redline MTL, but a knowledgeable friend is suggesting MT-LV which I haven't heard of before. I've been told I need 2 litres, but the Redline is sold in bottles of 946 ml... is 2 bottles enough or do I need 3?

Finally - gearbox mount - is it normal practice to replace this whilst gearbox is out?

Engine mounts - looking to replace these too. The originals look fine, but are 20+ years old if original, therefore good practice to renew?

Thanks

Nick

Tin Man
Tin Man's picture
Offline
Last seen: 1 week 6 days ago
Joined: 17/04/2014

Hi Nick

I use Redline MTL which was recommended by Road Race Transmissions.

I did change my engine mounts, but they looked ok.

I bought 2 bottles when I did mine. Opie Oils are competitive and offer a delivery service. I think we get a club discount too.

John

paul richards
Offline
Last seen: 1 hour 22 min ago
Joined: 17/04/2014

Redline MTL recommended for 6 speed. 
Inspect engine and gearbox mounts for condition/cracks. If no problem refit. No need to spend needlessly. Mine are 23 years old and still good. 

Paul Richards

LADS Joint AR  Drink

I thought 2020 was the year that was going to give me all I wanted. It turned out to be the year to make me appreciate what I've got.

Andy135
Andy135's picture
Offline
Last seen: 2 hours 45 min ago
Joined: 19/07/2021

For what it's worth I recently went for 2 bottles of Redline MTL for my 6 speed. Finding the time to take out the old and put in the new is a different matter though Wobble 

ScottR400D
Offline
Last seen: 2 hours 1 min ago
Joined: 23/08/2015

The fill is about 1.6 litres so 2 of the US Quarts (946ml) covers it fine. 

L7C
SLR No.77
SLR No.77's picture
Offline
Last seen: 1 hour 6 min ago
Joined: 17/04/2014

I use a normal GL4 (Comma) rather than MTL in my 6sp, I found the MTL caused the gearbox to be very noisy. Second gear is a slightly stiff shift when absolutely cold but in reality after only a mile or so of driving it works perfectly. I'd need some convincing to go back to MTL.

Caterham and Lotus Seven Club Leadership Team Member

The register for all numbered limited-edition Caterhams ....... www.thecaterhamregister.net ...... www.instagram.com/thecaterhamregister

John Vine
John Vine's picture
Offline
Last seen: 44 min ago
Joined: 17/04/2014

I've always used Comma SX 75w-90 GL4 in my 6-speed boxes.  The last batch came from Opie Oils (with Club discount).

Re new parts, certainly check the condition of the mount rubbers (g/box and engine/chassis) and replace if they are suspect.

I take it your clutch is in good order?

JV

Nick Bassett
Nick Bassett's picture
Offline
Last seen: 5 hours 16 min ago
Joined: 17/04/2014

Thanks for all advice etc.

Still not sure on whether to change engine & gearbox mounts - they look fine with no cracks etc.

JV - clutch plate was OK, but springs were broken, so have a new Helix going in. CRB was shot, but fortunately I bought an alloy example years ago that should do nicely!

Bolter, bolter, full power...

Superlight R # 81

Instagram: superlight_r_81

Graham King
Offline
Last seen: 5 hours 11 min ago
Joined: 17/04/2014

Nick, when I did a similar exercise on my engine a good few years ago, I replaced anything that I regarded as consumable, that included the mounts, given the amount that will have been spent on the engine refresh etc my view was replace all that type of thing whilst it was easy, and the increase in overall cost was marginal in reality. 

Each will have their own view I appreciate but that's what I did. 

Graham. 

Nick Bassett
Nick Bassett's picture
Offline
Last seen: 5 hours 16 min ago
Joined: 17/04/2014

Graham - thanks.

Makes good sense as you say.

Please tell your brother his old 7 is still going strong - well it will be once the engine & 'box have been refitted!

Cheers

Nick

Bolter, bolter, full power...

Superlight R # 81

Instagram: superlight_r_81