Thread: fairey overdrive

Manufacture of them by Rovers Down South ceased in December last year (see Rovers Down South Fairey Overdrive) so there is no 'new' price.

Second hand ones go for somewhere round $500-$1000. Mine cost $500 with a Landrover attached, but I had to spend nearly as much again on parts. Most parts are available, but many of them are expensive.

How strong are they? They generally withstand operation OK for standard Rover engines, provided they are only used in third and fourth gear. Operation in first or reverse can easily break them if used with full throttle and a sudden load such as losing and then gaining traction. But no different if used in low or high range.

If buying one second hand, ensure that all parts are there. Likely to be missing is the linkage and bracket for this, and the drive dog that replaces the gear on the mainshaft of the gearbox.

Problems. The oil reservoir is small, and oil can be chucked out the breather - I extended the breather. Oil level must be checked regularly, especially if the overdrive is used on the highway. The drive dog is susceptible to wear, and will eventually lose drive totally. While the dog is only US$125, the bit it engages with is the mainshaft, which is US$350, and wear takes place on both.

In my view, having had one for a number of years, I would not get one again. The Rover engines are quite happy to turn at the required revs for the 110kph speed limit, and the lower rpm resulting from the overdrive is only a slight advantage.

My advice would be that if you have a Rover engine, either four or six, forget the overdrive - its only real advantage is as a splitter, especially in low range. If you have another engine, perhaps look for another type of overdrive, although these are rarer and more expensive. For example Heystee Automotive Online Store

John

Originally Posted by JDNSW

In my view, having had one for a number of years, I would not get one again. The Rover engines are quite happy to turn at the required revs for the 110kph speed limit, and the lower rpm resulting from the overdrive is only a slight advantage.

My advice would be that if you have a Rover engine, either four or six, forget the overdrive - its only real advantage is as a splitter, especially in low range. If you have another engine, perhaps look for another type of overdrive, although these are rarer and more expensive. For example Heystee Automotive Online Store

John

I've got a "Roverdrive" on my Series 3. Made in Canada, and reputed to be fairly rugged. Not had it long, so can't comment on the durability. However, can be used in any gear (even reverse) and shares its oil with the transfer case (the oil level in the TC is lifted by half a litre and there is a dipstick as part of the kit). This may have overcome the Fairy problems with the oil.
I find it very handy when in hilly country as it allows you to find a gear that matches the climb, especially if its a long hill.
Cheers

Coop

Yes, the Roverdrive is reputed to be a lot better in all respects - but I have no experience with them.

John

thanks guys for your response, if the revs only drop a small amount i might not worry about it, especially running 35s

Originally Posted by army2a

thanks guys for your response, if the revs only drop a small amount i might not worry about it, especially running 35s

Hang on - 35s - what gearbox and tfr case are you running? I would have thought a series box would not survive very long with 35s.

If you have an LT95 then we are talking about a different Fairy Overdrive.

What Fairy Drive are you interested in - determined by tfr case.

Garry

army2a'

I bought one of these new in 1976 for $450 (I think), had it fitted by the LR agent in Orbost, VIC. The sales pitch at the time was that it could be used in all gears. I was a timber contractor then in the high country with a '68 88". I used that overdrive as a splitter in all gears, low or high range and often with four wheel chains on.
It lasted 18 months then stripped the gear as mentioned above. I had been advised to chuck the original mainshaft gear, nut and T/Case end plate under my seat, just in case.
Well I didn't and without them there is no drive and I took 2 days to walk home and a month to recover the vehicle. This is the only time I have ever walked home driving a 2A and I have not forgiven that Fairy.
I sold the bits for $25 and never looked at another one again.

However, with the advent of the internet I am surprised to see how many of these are still in use all over the world without too many problems (sort of). I still think they are a weak link and as other have said, have got by without since then quite happily. Sometimes, I feel I need a 5th gear, so if someone would buy me a Roverdrive I would give it a go. That seems to be a stronger bit of kit altogether.


cheers

Tom
1964 GS109

The Rover engines are quite happy to turn at the required revs for the 110kph speed limit

My '74 109 with 2.25 Petrol doesnt really feel happy at more than 75kph. All original gearbox diffs etc. 7.50 x 16 tyres. No idea what RPM it is doing.

Always fancied an overdrive to avoid the "Where's 5th gear" feeling, but she doesn't do much road work, so it's not worth getting one anyway.

It feels like it would explode if I tried for 110! But perhaps I am overly sensitive and just need to thrash it harder?

RJ

Originally Posted by army2a

thanks guys for your response, if the revs only drop a small amount i might not worry about it, especially running 35s

A 2.25 would seriously struggle with 35s AND an OD.

The fairey OD is noisy and weak. The Toro is quieter and slightly stronger. The roverdrive is better again, however if you are spending Roverdrive money, you would be better off with an R380 5-speed conversion.