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MG MGB Technical - Mgb GT transmission options

Can anyone confirm what transmissions were available for the RB 74 MGBGT. I am looking at one with a Leland 5 speed that was supposedly an option. Is there any documentation to back this up?
Brian Smith (1950 TD3376)

The MGB never had a 5-speed 'box as an option, only 4-speed with (optional) overdrive.
Dave O'Neill 2

Sorry Brian, you have been told rubbish. Only two manual gearboxes were ever fitted to the MGB. From 1962 - 1967 there was a 4-speed box similar to the one used in the MGA with no synchromesh on 1st gear. From 1967 to the end of production there was a 4-speed all synchromesh gearbox. Although there were some changes to the ratios in this box, the basic design was always the same. Either type could be specified with electrically operated overdrive as an option.

An automatic transmission was also available from 1967 - August 1973 when it was dropped. Automatics were rarely sold in North America and Canada according to Clausager in "Original MGB".

The same gearbox, suitably modified, was also used in the MGB GTV8 and the MGC. No 5-speed gearbox was ever fitted by the factory.
Mike Howlett

Dave and Mike tell it like it is. As I understand it, the majority of the Bs sold in the North American continent didn't have overdrive. Overdrive gives you effectively a 6 speed transmission with overdrive available on third and fourth (top gear).

However, more recently aftermarket companies have offered five speed conversions for MGAs/MGBs and maybe T types. The ones I've seen use a Ford Type 9 gearbox as used in the European Ford Sierra in the 80s/early 90s. Not sure if this box was ever used in a Ford ever originally sold in the States/Canada, but complete conversions have been sold across the Atlantic.
Peter Allen

For some reason only 17% of 4-sync cars were shipped to North America with overdrive, whereas for RHD and other LHD export it was 92% (figures in Clausager). Some time ago an American pal thought it was down to Americans not knowing what overdrive was, so they didn't want to pay extra for it.

Soon after production of the V8 started OD on 3rd gear was dropped as it overstressed the gearbox on the overrun. North American spec from from Feb 77 went the same way, although in that case it was to simplify the switching which were used to control the 'transmission controlled spark advance' system which operated in 4th gear only, as well as the OD.
paulh4

Thanks All, you have confirmed what I thought. I think owner was offered a "bill of goods" by the garage who installed it. The car is nice and I guess it can be converted back but will see.
Brian Smith (1950 TD3376)

If a 5-speed has been fitted and done well, why would you want to convert it back? It's less likely to give trouble than an overdrive.
Mike Howlett

Appreciate the comments. I went and viewed the car today and drove it around. The description was off base, it is a factory OD transmission operated from the stock. The car, while not a CB is in fantastic shape, drives well and has been very well taken care of. I'm sure the colour will grow on me........it is called red but looks orange.

At this time nothing requiring my attention other than minor items to make it mine. Yes, I bought it!
Brian Smith (1950 TD3376)

Result.

Photos please?
Dave O'Neill 2

Well done.

>>it is called red but looks orange.<<
Sounds like Vermilion.
Nigel Atkins

Or Flamenco.
Dave O'Neill 2

Or Blaze.
Peter Allen

Another reason the cars were not equipped with optional O/D is, petrol was so cheap. In the 60's and early 70's IIRC a U.S. gallon of fuel was $0.30 to $0.34 in the New York Metro area. Traffic in that part of the country was also another factor. The cost savings in fuel didn't justify the expense of the O/D option.

I do recall college days in Oklahoma, my then girl friend and I bought a 1950 Plymouth Special De Luxe for $90. Gas was around $0.21 to $0.26. There were many open roads with speed limits up to 70 MPH and long distances between cities.

The O/D option would have perhaps made more sense due high mileage and speed travel.

Cheers

Gary
79 MGB
gary hansen

Finally a GT! Sold my last one a couple of years ago and really missed it. The TD was great but after 19 years it was time to let someone else enjoy it, now I have a car that is dry, warm and comfortable. The Blaze colour is growing on my wife and I 😂

Brian Smith (1950 TD3376)

A 74 RB (strictly speaking a 74 1/2) GT would have been Blaze originally, Flamenco if a 75 model. Vermillion was 78-80. The Heritage certificate will tell you for sure ... which isn't to say it's still that colour!
paulh4

Thanks Paul. From all indications it is still the stock colour. It is a 74 1/2 that came with twin carbs and wire wheels. Very few with that spec here in Canada.
Brian Smith (1950 TD3376)

This thread was discussed between 26/02/2018 and 02/03/2018

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