LT230R or LT230T ratio change

[hurbie]

hello all , 

for the Eurover project i need a transfer box and i need some information and opinions,

my daily 110 has a 200tdi (discovery) lt77 and a lt230T 1.667 ratio , using 255/85-16 tyres it's a bit low on top end speed .

 

so i would like to get to a 1.44 ratio (as i think 1.2 is way to much) , i have at hand the original transfer case from the scottisch 110 (20d 1.667) from the french donor a 12D 1.667 , and from a mate a 43D 1.44 in need of a complete rebuilt (missing output bearing and flake's of copper in the casing).

after searching the internet i found that the 12D box is a LT230R , from the comments these seem even better as the LT230T , because the intermediate shaft is much bigger and prevent the casing from getting the hole elonggated.

 

now to the question , can the 1.44 gear's from the 43D been used in the 12D box ?

[smallfry]

I couldnt answer the question about swapping the gears, but the 1.22 ratio is no good for a 110 with a 200Tdi if you ever want to put a load on it. Or tow anything.

Unless you really like changing down a lot.

[Bowie69]

Check on the ashcroft site.... they have a serial number checker on there which will let you know what can done and how.

Incidentally, I have everything needed to convert an LT230 to 1.4 sitting a box in the shed, except the crush tube.

[hurbie]

33 minutes ago, Bowie69 said:

Check on the ashcroft site.... they have a serial number checker on there which will let you know what can done and how.

 

do you happen to have a link to this serial number checker ? i can't find it on the website

 

[Bowie69]

On all their ratio changing kits they ask various questions, e.g.

https://ashcroft-transmissions.co.uk/product/1-410-gear-set/

[hurbie]

1 hour ago, Bowie69 said:

On all their ratio changing kits they ask various questions, e.g.

https://ashcroft-transmissions.co.uk/product/1-410-gear-set/

noticed that , thought you meant something else ..

[Bowie69]

Apologies, probably didn't explain it very well

[uninformed]

The LT230R definitely has a larger diameter intermediate shaft as seen in this photo 

 

 

A friend who is very well versed in gearbox design and built more highly modified LRs than most of us, prefers the LT230R over the LT230T

 

The problem I see will be the availability of parts and especially aftermarket parts like ratio changes. For one, the earlier high/low hubs and selector rings are unavailable and are not the same as later versions. This immediately reduces ratio change options as the dog teeth are integral on the output gears, which are matched to the intermediate gears.
 

I highly doubt (99.783%) you can change gears. The transfer case final output ratios are a combination of input, intermediate and output gears. The high and low range output gears are matched to their corresponding intermediate gears. The 1.410 high range would have a different corresponding intermediate gear (size and tooth count) than the 1.667 gear set.

Not only will the later 1.410 intermediate gear not install in the earlier LT230R case, it would cancel the reason you are choosing it (intermediate shaft strength increase)

 

You would have to find a 13D case which is apparently the 1.410 LT230R

[hurbie]

13 minutes ago, uninformed said:

The LT230R definitely has a larger diameter intermediate shaft as seen in this photo 

 

 

A friend who is very well versed in gearbox design and built more highly modified LRs than most of us, prefers the LT230R over the LT230T

 

The problem I see will be the availability of parts and especially aftermarket parts like ratio changes. For one, the earlier high/low hubs and selector rings are unavailable and are not the same as later versions. This immediately reduces ratio change options as the dog teeth are integral on the output gears, which are matched to the intermediate gears.
 

I highly doubt (99.783%) you can change gears. The transfer case final output ratios are a combination of input, intermediate and output gears. The high and low range output gears are matched to their corresponding intermediate gears. The 1.410 high range would have a different corresponding intermediate gear (size and tooth count) than the 1.667 gear set.

Not only will the later 1.410 intermediate gear not install in the earlier LT230R case, it would cancel the reason you are choosing it (intermediate shaft strength increase)

 

You would have to find a 13D case which is apparently the 1.410 LT230R

thanks for your very good explanation !!

[uninformed]

In these two photos you will notice the high range output gears have different diameters and tooth count, and the corresponding gear on the intermediate gear set also has a different diameter and tooth count. That should tell us, we can’t swap a high range output gear between different intermediate gear sets.

 

On another note, the early input gears are not cross drilled. This was a problem that caused fretting corrosion on the input splines. You can drill them yourself though. 

 

1.410

 

1.667

 

 

Edited March 10, 2023 by uninformed

[hurbie]

so with the info at this moment i think my best bet is to rebuilt the 43D , with more parts availleble 

maybee put some money in it to sleeve the intermediate shaft , or leave as is and keep my eye's open for a 13D and swap when neccesary .

 

thanks for your input !

[uninformed]

The 43D should be a good option to rebuild. It has some advantages. If I’m correct that is a TD5 era case, it will have a stronger main case due to thicker ribbing in areas. It will also have a wider input gear (and corresponding intermediate gear) The input gear will be cross drilled and the bearing separation is greater than previous versions. 
 

Id definitely get the case sleeved for the intermediate shaft. Ashcroft sell the sleeves and they are a top hat design which IMO is important and definitely better than others that are not.

[Bowie69]

If you read the Ashcroft link, and the other ratio change pages, it tells you what you need to do which ratio change depending on your box's serial number.

I changed my early 1.4 box to 1.1 ratio with ashcroft parts (the high ratio gear set -low range gear, intermediate and selector hub). This 'upgraded' the box to the later spec at least in this respect.

The later still boxes are unknown to me though, the Ashcroft pages will let you know what's possible or not.

As mentioned, I have a 1.4 gear set here plus the intermediate and collar, which I believe should fit into the later boxes with a new crush sleeve.

[hurbie]

11 minutes ago, Bowie69 said:

If you read the Ashcroft link, and the other ratio change pages, it tells you what you need to do which ratio change depending on your box's serial number.

I changed my early 1.4 box to 1.1 ratio with ashcroft parts (the high ratio gear set -low range gear, intermediate and selector hub). This 'upgraded' the box to the later spec at least in this respect.

The later still boxes are unknown to me though, the Ashcroft pages will let you know what's possible or not.

As mentioned, I have a 1.4 gear set here plus the intermediate and collar, which I believe should fit into the later boxes with a new crush sleeve.

thanks for the replay , the Ashcroft website doesn't give me very good answers between the old "R" type and the newer "T" box'es , everything i read is regarding to the newer  boxes.

as it stands the easiest way at the moment is rebuilding the broken 43D box , have to take it apart to see what i really need parts wise , this box is allready a 1.4 , so there's no need for a ratio change .

(or i didn't get your replay right and you have a 1.4 ratio set for a old LT230R , then i might be interested)

Edited March 10, 2023 by hurbie

[uninformed]

42 minutes ago, Bowie69 said:

If you read the Ashcroft link, and the other ratio change pages, it tells you what you need to do which ratio change depending on your box's serial number.

I changed my early 1.4 box to 1.1 ratio with ashcroft parts (the high ratio gear set -low range gear, intermediate and selector hub). This 'upgraded' the box to the later spec at least in this respect.

The later still boxes are unknown to me though, the Ashcroft pages will let you know what's possible or not.

As mentioned, I have a 1.4 gear set here plus the intermediate and collar, which I believe should fit into the later boxes with a new crush sleeve.

Are you saying your 1.4 box was a LT230R with roller bearings on the intermediate shaft and you changed it to 1.1 with an Ashcroft gear set which included TRBs on the intermediate shaft?

[Bowie69]

Intermediate shaft remained the same, no bearings changed, just the crush spacer.

[Bowie69]

Re:what I have here, see the 1.1 ratio page and the note around early/thick and later/thin gears, I had the earlier set up so had to buy the additional parts listed here:

Quote

If you want to fit this ratio to a unit with a serial number before XXD226368E, you will have the thicker engagement teeth so you will also need FTC1084 (low range gear) and FTC382 (high/low hub).

Does that help?

I have a 1.4 gear, suitable low range gear and hi lo hub. Not trying to sell it to you, just saying what came out!

 

[uninformed]

21 minutes ago, Bowie69 said:

Intermediate shaft remained the same, no bearings changed, just the crush spacer.

Have another look at the first photo I attached, showing the two different intermediate shafts and their respective bearings. 
 

The shafts are different diameters so it’s impossible to fit TRBs onto the LT230R version that suit the LT230T intermediate gear set. On top of that, the LT230T intermediate shaft is smaller dia at both ends where it is supported in the case. So shafts and cases can not be mixed and matched. 

 

22 minutes ago, Bowie69 said:

Re:what I have here, see the 1.1 ratio page and the note around early/thick and later/thin gears, I had the earlier set up so had to buy the additional parts listed here:

Does that help?

I have a 1.4 gear, suitable low range gear and hi lo hub. Not trying to sell it to you, just saying what came out!

 

This is referring to the dog teeth only. Ashcroft do not make a 1.1-1 high range output gear with early wide dog teeth. (I asked lol)  So since that’s the ratio you wanted you would have had to buy the intermediate gear set, high AND low range output gears and hi/low hub with selector sleeve at the least. 
 

Unfortunately this doesn’t help the OP regarding swapping LT230T gears into a LT230R case and using bigger shaft with the roller bearing set up.

 

on another note, if your old hi/low hub and selector ring are in good condition I might be interested to buy it from you. 

[hurbie]

18 hours ago, Bowie69 said:

Re:what I have here, see the 1.1 ratio page and the note around early/thick and later/thin gears, I had the earlier set up so had to buy the additional parts listed here:

Does that help?

I have a 1.4 gear, suitable low range gear and hi lo hub. Not trying to sell it to you, just saying what came out!

 

what would help even more , is if you know the transfercase serial number these parts are from 😉