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R380 for 2.8l 300tdi upgrade. Needs upgrading?

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I am rebuilding my 300 tdi into a 2.8l using crank pistons conrods from a MWM International 2.8l engine.


My R380 gearbox worked well enough when it was taken out. Intend to put back in with the upgraded clutch parts. Should I do anything to the R380, or just replace/upgrade when it starts to show issues. Am seriously tempted by the Ashcroft upgraded R380 bearings, but would prefer to wait a while with that. A gearbox swap is easy enough to do, but not on a long(ish) trip, off course.

There is some radial play in the input shaft, I mave movie clips on my phone, if it would help. Output shaft seems to run smooth with no significant play.

Mainly use the Defender for local camping trips and some occasional towing, but longer trips are planned for, hopefully a 7 000-12 000 europe trip in summer.


Opinions please?



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I've lost count how many R380 I've put behind my 2.8TGV, it's at least 3, probably 4. Then again I've forgotten how many miles it's done, but certainly more than 200k. A lot of those were motorway miles at high speed, on big tyres andan overdrive. A fair amount of off road work, and some heavy towing work here and there as well.

If you are fitting the VNT turbo as well, the big torque increase at low rpm is where the trouble comes from. The torque increase is lower if you retain the wastegate turbo.

Either way, my take is the same, if you treat the drivetrain with some sympathy, generally the gearbox will be fine. If you treat the clutch and throttle like on/off switches, your gearbox will suffer. On my first (early suffix) gearbox, I snapped the output shaft. The second was swapped as a precaution after 50k due to noisy bearings.

If you feel your box is not A1 now, then take the opportunity to sort it. An engine rebuild, even to standard spec, has a way of finding the other weaknesses in your drivetrain, in my experience.

Clutch is potentially more of an issue. The usual '130/HD' clutch didn't cut it for me, I could make it slip at 80mph going uphill. Motor and Diesel offered  an improved HD clutch with their 2.8 kit. (They had already changed the clutch design in their kit once). That was fine, until the centre plate burst while offroad in Wales. By then M&D offered a thrid upgrade, which seemed expensive for what it was (and makes the gearbox noisy in neutral) but has lasted at least 150k so far and never given any trouble. Not sure what I would fit if I had to change it again.

Edited by TSD
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Thanks for good advice and explanation. I usually drive with mechanical sympathy, but then there's the missus... :blink:

A TGV is on the bench as well. I guess it goes on with the 2.8, if not before.

Looked around on the M&D Website without finding any uprated clutch, i guess I need to call them?


I am currently running a ZF 4HP22 with the Disco 300td engine it came with, but had decided to swap back to the R380 when the engine gets swapped back as a 2.8. I am open for suggestions on whether that gearbox would be a better option for longevity/reliability in this specific application.


Between the expenses of engine rebuild, recon FIP?, full size intercooler? I was hoping to be able to wait a year or so until I go the full uprated R380 from Ashcroft-route. In order to spread the money load a bit.

Is a complete teardown necessary to change the bearings of the input/output shafts? I guess a look at a workshop manual or Youtube could tell me that...


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During one of my gearbox changes, I acquired the adapter housing to run an external cooler. However, as an interim I put telltale labels on the engine sump, both gearboxes and the overdrive. On the R380 it's low on the casing between the cast webs, so should hopefully be in good agreement with the bulk oil temperature. I've probably been using them for 10 years, I've never seen the R380 indicate alarmingly high. I think I have seen 90C - that may have been after towing miketomcat and his camp trailer for 50 miles through mid Wales in mid summer :blush:

Previously (here) I said it had never gone above 82. I've seen various figures for maximum gear oil temperatures, but I doubt anything consistently below 100 would be an issue? Certainly I decided the complexity and increased risk didn't warrant it (more things to fail and drop all your precious oil when you need it most).

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