Jump to content

Series gearboxes


Recommended Posts

Accepting that series gearboxes are made of toffee, do we actually know what metal was used to manufacture the gears.

They seem to stand up to normal use OK, and if possible what grade metal is used for say 90 or RR boxes.


Link to comment
Share on other sites

i dont really know about series boxes but i suspect that hardening treatments are of a higher spec nowadays aswell as materials used etc.

i would think (and i'm speculating here) that modern stuff is probably made from EN8 and nitrided 58 to 62 HRC 0.1 minimum, which is a standard hardness rating for gears AFAIK.

Link to comment
Share on other sites

The material quality of series 1,2 and 2A boxes is actually quite high. Unfortunately the design quality is very poor, resuting in a box that has relatively long slender main and layshafts that flex under load, causing the teeth on the various pairs of gears to separate and break. The mainshaft flex also causes the bronze 2nd and 3rd gear distance sleeve to fracture, sometimes causing the retaining circlip to be pushed out of its groove, which then allows 2nd and 3rd gear to float backwards and forwards from drive to overun. There really is nothing that can be done to eliminate all the weaknesses.You can modify a scrap series 3 layshaft to fit into a 2A box. this will address the layshaft breakage problem but the mainshaft still flexes.Most series 3 gearboxes are horrific due to 1st 2nd synchro problems and popping out of those gears when engine braking down hills. The suffix D series 3 box comes close to solving most of those design faults but still has the weak mainshaft as it still employs the bulky obsolete 1930's design 3rd 4th synchro assembly.

Rover should have done what American truck manufacturers do and buy in their transmissions from specialist manufacturers who know what they are doing.


Link to comment
Share on other sites

Also bear in mind that many of the modern replacemetn parts available are made of chocolate. You cannot buy many genuine series gearbox parts these days!

Also bear in mind the youngest series boxes now are at least 20 years old. They suffer terribly from wear, and if you compare them to the standard boxes in may 70's cars they really were no better or worse. There just arent many 70s cars still around! Compare them to a mini gearbox for example. They're just as pants. Gear change is horrible, mainshafts shear etc etc.

They were designed in the 50's and were onyl ever designed for the power of a 2.25 running on 6.00 tyres......

Nuff said......


Link to comment
Share on other sites

Mines a 1981, ex military 40,000 Km on the clock, nearer 50,000 now so hasn't done too many miles yet.

I have two series 2a boxes in the garage anyway, should both be original may look one day to see what they are like.

Synchros are going on mine, just have to double declutch, not that difficult.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy