rick130
20th April 2008, 01:01 PM
I've read Dave Ashcrofts description of the differences between the 'J' and 'L' 'boxes,
Ashcroft Transmissions (http://www.ashcroft-transmissions.co.uk/part_2.html#pa1)
R 380 Development
The R 380 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 bearings were used on the layshaft and the mainshaft, wider gears, bigger diameter syncro rings, syncromesh on reverse and a longer mainshaft spline.
This suffix J did unfortunately have a couple of design flaws which gave the R 380 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 that is used currently. The J and 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.
Just wondering what was different in the 'K' 'box, seeing as my very late '98 has one !
Ashcroft Transmissions (http://www.ashcroft-transmissions.co.uk/part_2.html#pa1)
R 380 Development
The R 380 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 bearings were used on the layshaft and the mainshaft, wider gears, bigger diameter syncro rings, syncromesh on reverse and a longer mainshaft spline.
This suffix J did unfortunately have a couple of design flaws which gave the R 380 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 that is used currently. The J and 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.
Just wondering what was different in the 'K' 'box, seeing as my very late '98 has one !