I will try & clarify this query from Brian Sanborn as simply as possible and
put to rest
some poor advice often given about reassembling the J o/d onto an early (pre
74) transmission.
You can fit ANY complete TR/Sedan o/d box into ANY TR given patience and
moderate
enginnering skills. The Stag or Sprint o/d boxes take even more effort as their
input
shafts are longer. The sedan and Sprint boxes use a 1" input spline. the Stag &
TR use
the larger 1 1/8" spline.
All 4 syncro boxes are the same length give or take a few mm, so they all fit
in the
same place and the tailshaft spline takes up slack either way.
Moss UK sell a kit of brackets to fit a complete Sedan or TR6 J o/d box into a
pre 75
TR6 chassis. The rear mount is quite a bit rearwards from the A type o/d or 4
speed.
Alternatively, you can hack off the old brackets on the chassis and make new
ones. It is
not very difficult, but you should ideally get the the rear mounting plate with
the o/d
box.
The sedan A type box does not fit easily as it has an offset vertical mount
rather than
the flat TR type. Some more fancy bracketry will however fix this. A bigger
problkem is
that sedan speedo gears are quite different.
If I recall correctly, all tunnels will be OK for either o/d. Cars orignally
fitted with
an A type o/d (pre 74) had a removable tin covers to allow access to the
solenoid
adjustment and speedo drive. I've seen cars with 1 and both covers fitted from
new, so I
guess there was the usual factory confusion.
The J o/d mainshaft will not however properly suit the gears/brass bushes
inside
TR4-4A-250-early 6 boxes, as nearly all J o/d mainshafts were designed for the
steel
bushed gears, which are not fitted to TR's pre 74 (approx). Also, some J o/d
shafts have
a different size input shaft bearing. The very first few Sprints and some Stags
had the
combination of J o/d and brass bushed gears. I do not recall ever seeing a TR6
with this
combination, but there probabaly a few. This is a big trap for amateur
rebuilders and
whilst you might get it all together, it won't last
Unless you are expert in these boxes, 20+ years of ecperience with these
suggests you
fit a complete box with o/d. Don't try and adapt late shaft & O/d into a pre 74
gearbox.
Terry O'Beirne
GT6 TR5 2.5PI racer etc etc
***** English Spare Parts *****
You neeed ESP!
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