Ah, I see. I thought they were both cable driven. Keep it though - if you ever change to a TD5 speedo in the defender, you need an electronic feed so may want to refit the black one at that point (although the sensor isnt the same between defender and disco from memory).
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RWD3M
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What Neil says. If you mate that to the original it'll likely destroy one or both. The gears should be changed as a pair.
julianf
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Is this something you know with certainty, in relation to the LT230 box, as its not something ive ever read.
What I'm asking is very specific - are you answering in general terms as to what you suspect is the case OR do you have knowledge of the LT230 and are speaking from a position of factual knowledge on the device?
This isnt a confrontational question at all - i just need to know with certainty, as in my reading, this issue has not cropped up in relation to the LT230 but it may just be that ive missed it, hence wanting to be sure.
They are interchangeable for the LT230 as far as i know.
I was also wrong to associate the gear with the transfer box ratio from what I just read - it sounds like the gears need to be matched to diffs and tyres not the transfer box as they all sit on the output side of the box (so I guess revolutions there are the same regardless of the ratio of the box)
How to replace the speedo drive gear on a Land Rover - Land Rover Blog
I have been without a speedo for sometime now, and been relying on the GPS to tell me what speed I was travelling. So, unable to put up with it any longer, I got a new speedo cable and spent 30mins replacing it last week. When it didn’t fix the problem (speedo was still not …
www.land-rover-blog.co.uk
Speedo gear
Hi When going through villages with speed recorders the figure shown on the roadside display always appears to be lower than what my speedo shows. Can anyone tell me which colour (teeth number) speedo drive gear I should have in my 300TDI defender 90 fitted with 235/85 R16 tyres and discovery 1.2...
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julianf
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They are interchangeable for the LT230 as far as i know.
I was also wrong to associate the gear with the transfer box ratio from what I just read - it sounds like the gears need to be matched to diffs and tyres not the transfer box as they all sit on the output side of the box (so I guess revolutions there are the same regardless of the ratio of the box)
How to replace the speedo drive gear on a Land Rover - Land Rover Blog
I have been without a speedo for sometime now, and been relying on the GPS to tell me what speed I was travelling. So, unable to put up with it any longer, I got a new speedo cable and spent 30mins replacing it last week. When it didn’t fix the problem (speedo was still not …
Speedo gear
Hi When going through villages with speed recorders the figure shown on the roadside display always appears to be lower than what my speedo shows. Can anyone tell me which colour (teeth number) speedo drive gear I should have in my 300TDI defender 90 fitted with 235/85 R16 tyres and discovery 1.2...
Yep, the speedo gear is irrelevant of the cogs in the boxes - its on the output drive. So it, effectively, measures prop rotation. Diffs and tyre size are what its matched to.
Again, im swapping it because the hole on the top of the black gear mates up with the discovery electronic sender, whilst i want it to mate with the defender mechanical cable. Ratios are neither here nor there for me really (and i dont even know if the blue/green cog will match my wheels, but at least it will make the dashboard do something, rather than nothing)
RWD3M
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Not speciffically the LT230 but certainly the R380 and the LT77.
I've no specific experience of the LT230 box, I was just going off what I've seen on other cars. I suspect if you count the teeth on the black and blue/green gears they will be different?, Also if the mating gear (worm gear?) has a different pitch then the helix angle on the black and blue/green gears will be different, from what I can make out from Post #18 that looks to be the case?
Slightly OT but this is a common thing with classic mini's; they have all sorts of different ratio speedo drives for the different final drive ratios; 5,6 & 7 teeth worm gears and 16,17 & 18 tooth pinions.
Can you get to the 'other' gear in the casing and maybe swap that as well so you are keeping the matched pair together? There might be a speedo error if the ratios are different but at least it won't destroy itself!
Its a common part to disco, RRC and Defender though so the one in there will be the same as the one in Julian's defender transfer box. Item 2: https://parts.jaguarlandroverclassic.com/frc3162-gear-speedometer-drive.html
Better picture here: https://www.shop4autoparts.net/parts/transfer-box/frc3162-speedo-worm-oem/ (better price too - they are as low as £30 for Britpart)
Going off that first link and looking at the parts diagrams, plus a bit of Googling similar part numbers, brings up four different pinions! FRC3310 (20 teeth, blue), FRC3311 (21 teeth green), FRC3312 (22 teeth, yellow) and FRC3313 (23 teeth, red). Can't find any black ones though! I can only find one worm though, but surely they can't all mate with the same worm? @julianf what is the teeth count on your two pinions and are they the same diameter?
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OJCar
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On the LT230 Transfer box the different ratios needed for the speedos are by swapping the speed drive gears .
There are various part numbers for the speedo drive gears eg. FRC3312 22 teeth yellow gear , FRC3310 20 teeth Blue gear
They mate with the Speedo Drive Gear wheel FRC3162 of which there is only one part number.
You do not change the Speedo Drive Gear Wheel to change the speedo drive ratios on the LT230.
(Advice from experience not Google !)
There are various part numbers for the speedo drive gears eg. FRC3312 22 teeth yellow gear , FRC3310 20 teeth Blue gear
They mate with the Speedo Drive Gear wheel FRC3162 of which there is only one part number.
You do not change the Speedo Drive Gear Wheel to change the speedo drive ratios on the LT230.
(Advice from experience not Google !)
OJCar
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@OP, If your speedo drive casting has been damaged I may be able to get you a second hand replacement if you are stuck.
BTW Various Ford gearboxes used this same system, just change the speedo drive gears for different ratios.
There was a Van Hire place in Edinburgh that used this to try and shark their customers.
Charged hire by the mile, speedo odometers that over read.
When I hired one of their vans to help out the GF, the speedo over read so badly that it claimed I was doing 45ish mph around the bend in Ravelston Dykes Road in a mk2 Transit.
(I pulled over, disconnected the speedo cable till I was just around the corner from returning the van to them, sulky faces when they read the odometer ! Cheating skunks ! )
BTW Various Ford gearboxes used this same system, just change the speedo drive gears for different ratios.
There was a Van Hire place in Edinburgh that used this to try and shark their customers.
Charged hire by the mile, speedo odometers that over read.
When I hired one of their vans to help out the GF, the speedo over read so badly that it claimed I was doing 45ish mph around the bend in Ravelston Dykes Road in a mk2 Transit.
(I pulled over, disconnected the speedo cable till I was just around the corner from returning the van to them, sulky faces when they read the odometer ! Cheating skunks ! )
