Thread: LT230 compatability

Originally Posted by sdt463

Thanks every one. At the moment its just an idea i'm kicking around.
At the present time I have a Roverdrive fitted to the standard defender transfer box and it does a great job leting me tow my 3.2 ton van in 4th overdrive to protect 5th gear, but the egt's often tell me the gearing is to high in overdrive and the speedo tells me its to low in 4th.the disco LT230 would split the diference.
Trouble with the disco box will be having to slip the clutch more in 1st to get the rig moving.
Cheers all Dave
Ps are all the LT230 imput shafts the same size.

I wonder if you towing practice will change the poor strength issue from 5th gear to the Roverdrive.

Also for towing, as has been mentioned, the LT230Q from many disco I's and all disco II's are weaker.

All LT230's have the same spline size in the input gear. However Land Rover increased the length of the spline to reduce a wear problem that was frequent with earlier LT230's.

Just going through this.

The 28D prefix are D1 LT230T (tapered roller bearings) boxes with different ratios depending upon suffix letter.

• Suffix E and earlier are 1.222:1 with 26 teeth input gear.
• Suffix F are 1.214:1 with 28 teeth input gear.
• Suffix G are 1.211:1 with 38 teeth input gear (same ratio as Ben's but his is a LT230Q (Quiet)).

Originally Posted by Lotz-A-Landies

...[*]Suffix G are 1.211:1 with 38 teeth input gear (same ratio as Ben's but his is a LT230Q (Quiet)).[/LIST]

Diana - 38 tooth input is a Q case.

Hi Ben

We've had this discussion before, I thought yours was a 36D LT230Q 2.11:1.

Have we had documentary confirmation that the 28D LT230 with 1.211:1 ratios were T or Q? (other than Ashcrofts who's website calculator has been condensed to suggest the LT230 in a D1 were RRc and had only one ratio)

I'm only going by the document (posted above) from the JRA training manual.

Diana

Originally Posted by Lotz-A-Landies

Hi Ben

We've had this discussion before, I thought yours was a 36D LT230Q 2.11:1.

Have we had documentary confirmation that the 28D LT230 with 1.211:1 ratios were T or Q? (other than Ashcrofts who's website calculator has been condensed to suggest the LT230 in a D1 were RRc and had only one ratio)

Diana

My case was indeed marked 36D, however had a 38 tooth input gear. A 38 tooth input gear using T-sized teeth would not fit in the case. ALL LT230T's have either a 26 or 28 tooth input gear AFAIK - even the 1.003 ratio.

e.g. http://www.ashcroft-transmissions.co...od&productId=8

Click for company profile

About Us | Contact Us | How To Order | Terms & Conditions
Location: »DIY Rebuild kits» LT230 REBUILD KITS

Input gear
Input gear

Product Information

We can supply both the earlier (26th tooth) and later cross-drilled (26th and 28th tooth) input gears.

To identify which type you need you will need to look at the your transfer case serial number. The last letter of this will denote whether your vehicle is able to accept the later cross-drilled type. A transfer box with the suffix A or B will only accept the earlier 26th tooth, non cross-drilled type (FRC5428). A transfer box with the suffix C onwards will accept the later cross-drilled type. See below to find the serial number :

Defender Guide :

Suffix A or B uses a FRC5428, not available cross drilled @ £ 45

Suffix C to F uses a FTC5089, cross drilled @ £ 45

Suffix G, 300 TDi or TD5 uses a FTC4962 @ £ 65,

Suffix G, 2.4 TDCi uses a IEH500010 @ £ 65,

Disco Guide :

Suffix C to serial number 308626E uses a FTC5089, cross drilled @ £ 45

Serial number 309143E to 551442F uses a FTC5087 @ £ 45,

Suffix G uses a IEH500010 @ £ 65,

If you look up the IEH500010 you will see it is the fine tooth LT230Q gear, the same as fitted to my (broken) case.

e.g.

INPUT GEAR 38 TEETH Q TYPE LT230 OEM 135mm

Input Gear for Transfer Box LT230 'Q' Type Defender V8 1.2 Ratio & Discovery II 1.2 Ratio

38 Teeth 135mm Overall Length

Fits:-

Defender V8 1.2 Ratio From 2003 Suffix G on Boxes
Discovery II 1.2 Ratio Suffix G on Boxes

Note This Gear does not have dog teeth drive gears for PTO so is not suitable if your vehicle has, or you intend to fit a Power Take Off unit.


IEH500010

http://www.shop4autoparts.net/Defend...0_Q_135mm.html


Happy now???

Originally Posted by isuzurover

My case was indeed marked 36D, however had a 38 tooth input gear. A 38 tooth input gear using T-sized teeth would not fit in the case. ALL LT230T's have either a 26 or 28 tooth input gear AFAIK - even the 1.003 ratio.

Not suggesting you're wrong, but would like to see something from Land Rover UK that confirms the change over.

I know it seems odd to me that they would have different casings (to fit the different inputs) but use the same prefix. Logic would suggest that the Q case would have a different prefix, however the page I posted up came from JRA so errors wouldn't be a surprise!

Originally Posted by isuzurover

...
Happy now???

Haven't been unhappy for weeks!