P38 V8 manual gearbox to P38 Diesel (M51)

[fosha]

Hello Guys,

New here, hope to learn a lot from here. Also if there are any rules about the forum I am breaking, please let me know.

So I bought a Range Rover P38 1996, But it has a gearbox problem. I found out the previous owner installed an R380 64A-J one. which I believe was from P38 4.0. And P38 were very few in my country. So local parts a super expensive and also shipping the whole thing due to weight it is also expensive. The question is,  can we convert the R380 64A-J to R380 65A? If yes, please help out with the parts numbers.

Thank you

[Escape]

Welcome to the forum!

You can use an R380 from a V8 on a diesel, but you have to swap over the input shaft. Which means opening the box, so you might as well just do a rebuild on the box you have. First gear is also different, the diesel has a lower ratio.
What exactly is the problem and why do you want to swap? Do you have another box available?

As for the type, the P38 used 64 and 65A (both type D) as far as I know. With suffix J, K or L depending on the model year. Those are all interchangeable (for the same engine). The suffix has to do with internal improvements, not whether it's for a diesel or V8. 

Filip

[fosha]

Thank you for the feedback, the current gearbox is for P38 V8. The car has problems with gearing so I thought to change the gearbox(64A) to its standard one (65A) and see.  Also, I will install a new clutch and slave master cylinder just to be sure.

 

[Escape]

I compared both versions when rebuilding my box and the input shaft it too different between the diesel and petrol to get a good fit. Not sure which was the bigger/longer of the 2. I guess you could fit the smaller one instead of the bigger, with a appropriate clutch disc, but it would not be an ideal solution. So either the 64A box that is in your car has been rebuilt with a diesel input shaft, or the clutch setup has been modified. If you replace the entire clutch pack, you should have no problems fitting a 65A.

Edited to add: clutch slave is identical and master interchangeable between diesel and petrol, but the bellhousing is different. The smaller diesel bellhousing uses a shorter shaft for the same clutch fork. But it's unlikely that has been changed, so should still be original.