Installation Information » (Click to Expand Collapse)
Bias Adjustment
It is important to check the bias adjustment particularly on the defender boxes if a "notchy" selection on 3rd or 4th is a problem.
The bias plate and springs are pre set on the (short stick) Disco and Range Rover boxes, so should need little or no attention, but if there is a problem selecting 3 or 4 it is possible to move the spring location plate which is held down by the 4 x M8 bolts under the top dust cover.
The"long stick" boxes, Defender and early Range Rover, come without the "turret" assembly. Always check the turret is in good condition ie locates in the socket and feel firm. The 3 and 4 selection is by two "bias" adjustment springs located one each side of the turret under the rubber boot. Pull the boot back and if necessary adjust the two M6 screws under the springs, the lever should self center in the 3 - 4 position.
Other causes of poor selection are "dragging clutch" and "tight spigot", both of these problems will show on the R 380 by tight gear selection in all gears.
Technical Information / FAQ's » (Click to Expand Collapse)
R380 Development
The R380 was introduced in 1994 with the suffix J which was a significant improvement on the LT 77 it supercedes> Differences included a steel oil pump (as opposed to the LT 77 fibre one), an additional 2 support bearing, used on the layshaft and the mainshaft, wider gears, bigger diameter synchro rings, synchromesh on reverse and a longer mainshaft spline.
This suffix J did unfortunately have a couple of design flaws which gave the R380 some bad press, they were prone to the mainshaft shearing across the oil feed holes, the layshaft also sheared at a stress concentration behind the sandwich plate causing loss of 5th and reverse also early ones still suffered from mainshaft wear until the cross drilled transfer case gears became fitted as standard on the suffix G transfer cases.
In 1999 the suffix K was used very briefly for a few months then came the suffix L. The K and L are virtually identical, the only difference I have found is the L outer main casing has an additional strengthening rib, internals are the same. The J and K/L are very different, 2 of the bearings were substantially uprated and pinion and layshaft teeth were widened again, this results in a much stronger unit.
Cooling
It is not abnormal for the R380 to run quite hot and this often results on either baulking or sticky shifts which can often be improved by either an oil additive or different oil.
If you feel your unit is running too hot then bear in mind Landrover make for 2 main markets, Europe and Rest of World (ROW), the ROW spec TD5 Defender and Disco gearboxes are oil cooled but Europe spec are not, there is some debate as to whether they should be, especially if you live in south Spain or Italy Etc.
The temperature the box runs at will have an effect on it's lifespan, please have a look in the misc section for details of the 'Oil Cooler Kit'
Related Products
Customer Reviews
Average Rating: 5
R380 gearbox
I have recently taken delivery of an R380 gearbox and fitted it a few days ago. My old one, after 140,000 miles had become very noisy, especially on the overrun, such that I was unwilling to trust it on long journeys. I selected the heavy duty bearings and raised 5th gear ratio for my new box. So far everything is going well with 300m miles completed, includign a great many junctions and traffic lights so lots of opportunities to go up and down through the box. Compared to the old one, the gearchange is a little tight and notchy, but that's because everything is very new. It has freed up somewhat as I've been running it in - either that or I'm getting used to it! The higher 5th gear is a good motorway ratio, giving flexibility but without overly high revs in the 60-80 mph range, so filtering into faster moving streams of traffic for overtaking or joining carriageways is effortless. As I've only done a few hundred miles, I can't comment on longevity yet, but I hope to be able to live with it for another 140,000 miles. I'm still deciding whether to return the old unit and claim the core charge back or buy an overhaul kit and repair it so as to have a spare.
John Brown :: Feb 23 2021, 11:29 AM
Rebullt Ashcroft Gearbox for my 1999 D2 TD5
The 1st/2nd gear syncromesh on my 1999 Discovery TD5 failed early this year(2020)at 156k miles.
MiD Engineering of Wantage organised and fitted an Ashcroft rebuilt unit with heavy duty rear support bearings and the higher ratio 5th Gear. They also activated the manual difflock.
The higher 5th gear transforms motorway driving, its quieter, the engine is less 'busy' and mpg is a bit better too.I thought there might be a 4th to 5th gear 'flatspot' although the engine has been tweaked but its not noticeable.
Thank you Ashcroft.
Simon J :: Aug 14 2020, 13:29 PM
New R380 for my Defender
I have bought a rebuilt R380 gearbox to replace the old noisy unit in my 1995 Defender 110. Placement of the order and communication with the Ashcroft customer service was a pleasure - very professional staff. International shipment went flawlessly. The resent exchange unit was reimbursed immediately.
Now my old Defender drives like a new truck thanks to the gearbox from Ashcroft!!! All in all I wholeheartedly recommend Ashcroft Transmissions as a source of high quality Land Rover parts!
Jaroslaw Bis :: May 20 2020, 18:54 PM
New R 380 gearbox
Hi Julie,
Just got home from collecting my Landrover & I have to say what a first class job ! well done. The gearbox is quiet & the gear change is like new unlike the last replacement I had from a main dealer ( xxxxxx'x Landrover xxxxx xxxx ) which was very noisy right from the start & the gear change 'sloppy' & when I complained I was told ' thats the best we can get it ' + it lasted only 52,000 miles ! You did a great job at a fair price, thank you.
Best regards
Murray
http://flintrefinishing.co.uk/
