Thread: 4BD1 into Defender

I posted a reply to Hellonwheels in the military section but it's probably of more interest to people here. KLR are in the testing phase of an r380 behind a 4BD1 using the LT95 bellhousing altered in some way to join the two. So this means that the hard-to-find LT85 bell housing is no longer required.

If you are satisfied that the r380 is strong enough, this will be very interesting news as it could make for a cheap and easy 5 speed conversion; and the r380 has a much nicer spread of ratios than the Isuzu boxes to boot.

Originally Posted by workingonit

Hellon, yes, I've spoken to KLR, they sell the gear driven power steering pump you can attach to the engine - something for later.

Seen my equivalent of 'war and peace" - "worn and in pieces"?

http://www.aulro.com/afvb/isuzu-land...t-adaptor.html

I have already fitted a PAS, makes all the difference in the world. Bought it from KLR and supplied my own steering box/resovoir.

Originally Posted by Dervish

I posted a reply to Hellonwheels in the military section but it's probably of more interest to people here. KLR are in the testing phase of an r380 behind a 4BD1 using the LT95 bellhousing altered in some way to join the two. So this means that the hard-to-find LT85 bell housing is no longer required.

If you are satisfied that the r380 is strong enough, this will be very interesting news as it could make for a cheap and easy 5 speed conversion; and the r380 has a much nicer spread of ratios than the Isuzu boxes to boot.

That's very good news. The R380 is purported to be strong enough for the job and is a nice driving box also. They did advise that a turbo would be almost necessary after fitting the 5 speed, just to get it into No 5 cruise rpm. Cheers for the update.

Hellon, saw "Darwin Harbour" - I think the penny has just dropped - are you the guy that let me have a look at the Isuzu mounts, and I helped you with the roll bar? Believe it or not I only recently built the mounts.

Originally Posted by Hellonwheels

That's very good news. The R380 is purported to be strong enough for the job and is a nice driving box also. They did advise that a turbo would be almost necessary after fitting the 5 speed, just to get it into No 5 cruise rpm. Cheers for the update.

My Defender has about 250,000ks on a factory turbo4BD1T/R380. almost always fully loaded, and almost all long trips in the bush/desert

FWIW C H T

Originally Posted by C H T

My Defender has about 250,000ks on a factory turbo4BD1T/R380. almost always fully loaded, and almost all long trips in the bush/desert

FWIW C H T

yet someone else on here (justin?), broke at least one R380 behind a 4bd1t, and others have broken them behind tdis and td5s.

I have had a good run from my lt85 but if and when it fails I won't be replacing it with an lt95, lt85 or r380.

I think for the Rover boxes it will be a case of regular rebuilds and don't labor 5th gear - if you haven't broken one then you are probably a good judge of the right gear for the right job?

Someone supposedly in the know told me that the Rover gearboxes behind the army 4bd1s were refurbished/re-engineered at great expense ie x-rayed for cracks, machined for bigger bearings etc. But I have not heard anyone on this forum talk of differences between the civ and mil spec 4 speeds.

Really?! They are several discussion/ threads.
Do a search for 'LT95A' and modifications.
In short: taper roller bearing conversion on intermediate shaft, return holes drilled as required for drain back from xfer to gearboc etc.