diff swap opinions

[73series88]

hey everyone
ive been thinking about the roverdrive for the series, but there so expensive. and im not sure on the reliability of the fairey od
someone near me has a set of 3.5 RRC diffs for sale, that are supposed to
be able to basically make my rover permanitaly in an overdrive state
for alot less than either any ods out there.
i dont really do alot of offroading, so thats not an issue.
i live in ct so i have hills here.
thanks
aaron

[rejeep]

Roverdrive well worth the $$$..

Its nice to have the gearing options and ability to split gears..

Up here in Rochester there aren’t a lot of hills, but I find myself splitting gears and needing more umph often..

I grew up in Woodbridge CT.. I know the area well.. I would not want to drive around permanently in OD...

Would make slow, slower, and just plain not fun..

my opinion of course..

[gambrinus]

3.54 diffs + a 2.25 engine = epic fail. It's too high of a ratio for the engine to deal with. The slightest hill will feel like Mount Everest.

Save your pennies and buy the Roverdrive.


RW

[LR Max]

Roverdrive, you get what you pay for.

Fairey's are actually a lot tougher than people give them credit for. Also carry the bits you need to swap it back, and you'll be fine. Only problem with a Fairey is that it is LOUD!!!

Only time you use an OD is on the highway. Rest of the time the standard rover drivetrain is good. Adding 3.54 diffs will ruin that. Unless you've got a bigger powerplant.

[TedW]

Very reliable, and not that noisey, IMHO. Just use synthetic 90w and you'll be fine.

BTW: I've never heard a negative word about the Roverdrive. But maybe I'm just not listening. If I was in the market today, I would probably go with the Roverdrive. But my Fairey is going strong and I am very happy with it.

[mongoswede]

Aschcroft in the UK has some other R&P ratios available for rover axles that I think will work with series trucks...you might have to run the Range rover carrier. I think the cost is per ring and pinion so double for a front/rear set (195 BPD). http://www.ashcroft-transmissions.co.uk/index.php?act=viewCat&catId=12 The 4.37:1 would probably work well.

[yorker]

I wouldn't do it but in the UK it is a common modification, even with the 2.25 diesel!!? If nothing else you could buy the diffs and try it out- it isn't that hard to swap. Then if it isn't for you swap back.

[tmckeon88]

I also would push for the Roverdrive. I put one in last year and it has been great - quiet and reliable. Again, the highway is where you mostly use it, and splitting gears when climbing hills.

[Tim Smith]

The Roverdrive is well worth the money. Not only do they work very well but Ray is easy to get in touch with if you do have any trouble.

I called him up a few weeks ago to help clarify something for a transmission rebuild I was doing. In the call I noted that one of the batwing washers inside my Roverdrive was getting loose and will probably need to be replaced soon. To this Ray said:

Oh! That sounds like a high mileage unit. If you don't mind sending it in when you get through with your travels, I'd love to show it to the boys and we can rebuild the unit for you. We don't get many units sent back to us.
If that isn't telling about how robust they are, I don't know what is.

[Donnie]

The Roverdrive is well worth the money. Not only do they work very well but Ray is easy to get in touch with if you do have any trouble.

I called him up a few weeks ago to help clarify something for a transmission rebuild I was doing. In the call I noted that one of the batwing washers inside my Roverdrive was getting loose and will probably need to be replaced soon. To this Ray said:

Oh! That sounds like a high mileage unit. If you don't mind sending it in when you get through with your travels, I'd love to show it to the boys and we can rebuild the unit for you. We don't get many units sent back to us.
If that isn't telling about how robust they are, I don't know what is.
the batwing washer that you speak of . Is it a slip in , like split & installed w/o pulling the pin or does it have a hole thru the washer for the pin? can you get a picture of it up?How many pinions are in this planet?

[alaskajosh]

3.8:1 available from KAM duplicates Roverdrive ratio almost exactly. Swap the right bits from a suffix B transfer case and your low range will stay right where it's at. It's the magic bullet. All for relatively cheap and stupid simple reliable.
I wouldn't go any higher than those 3.8s if I were you.

[Tim Smith]

the batwing washer that you speak of . Is it a slip in , like split & installed w/o pulling the pin or does it have a hole thru the washer for the pin? can you get a picture of it up?How many pinions are in this planet?
Sorry I forgot to take a picture of it. I can tell you that is is not a slip in. In fact Ray said it would be a pretty tough job to replace it without some of his speciality tools. I can't remember how many pinions are in the planet either.

[dabawei]

Hello,

I am looking for advice in upgrading my series 2a 1966 diff. my series-2a is reach hardly 50Mph on 4th gear. where wondering others is hitting 60Mph!

I did last year fully rebuild from A-Z; therefore, I am assuming transmission running normal.

I do not prefer Overdrive and it is not available in our region (Middle east) and shipping is costly. My usage mainly on street and sands dunes.

I read that Discovery 3.54 Diff will not help, as I notice on original series diff with long and steep bridge speed is decreasing with 4th gear.

Therefore, how many mile/hour it would add if I use the ASHCROFT 3.75 or 4.12?:confused: AND what is your opinion on output torque if I use 3.75 OR 4.12?:confused:

thanks

[yorker]

Hello,

I am looking for advice in upgrading my series 2a 1966 diff. my series-2a is reach hardly 50Mph on 4th gear. where wondering others is hitting 60Mph!




What other vehicles are you running with? If they are later 4x4's like V8 powered Land Rovers or Toyota Land Cruisers the old IIa will never really keep up at higher speeds. That said you should be able to do more than 50mph at least on flat sections.

IIa's are geared the way they are to make up for the relative low power and poor aerodynamics. You could put in 4.12's or 3.95s or other gears but it will make up for the fact that the engine is what it is. Top speed may technically increase but the ability to hold that speed on inclines won't be better.

[bugeye88]

I'm with Ted. I have had a Fairey for years and its been reliable and not that noisy. Keeping the oil up is key as they don't have the largest reservoir for the 90 wt. That said if you find a NOS or refurbished Fairey unit for a reasonable price, go for it. Of course the problem they are out of production, but there are plenty of parts available. The Roverdrive is undoubtedly an excellent unit if the funds are there.
Rob

[dabawei]

What other vehicles are you running with?

Top speed may technically increase but the ability to hold that speed on inclines won't be better.

Other vehicle are other landrover series in this forum! I think it is Series-3.

I believe existing diff is 4.7 is it correct? Therefore if I upgrade to 4.12 would it give relax engine with 50Mph and hold on normal incline?