Through my own experience restoring these cars for almost thirty years, it
seems that the later upgraded rear axle was fitted to most of the B spec and
all C spec cars.
In the spare parts book it is classified as “second condition axle”. The
basic differences are as follows:
Early cases had 3 filler/drain plugs e.g. one on the top, one on the bottom
and one in the back cover. This was specified as “condition one axle” in the
This axle also had a different pinion shaft and bearings along with smaller
crown wheel support bearings.
The spider carrier is also different having smaller diameters for the
Later cases had two filler/drain plugs e.g. one underneath and one in the
back cover (being the filler plug).
This axle had a much stronger pinion shaft and bigger bearings along with
larger crown wheel support bearings and stronger spider gear carrier
If you have access to an original parts catalogue and check the part number
for the first and second condition axles, you will note that the different
part numbers confirm my findings as stated above.
Another small detail (for info only) I found on the two types of axles is
that the two axle tubes that are pressed into the centre casing are “stake
welded”, to retain them. The early axles had two “stakes” and the later
ones four “stakes” to retain each tube. (Thus making them more BEEFY???)
The reason for these extra welds was to eliminate fractured welds, causing
the tubes to rotate in the centre casing, usually caused by over zealous use
of power and clutch in trying to emulate a Le Mans start! I have come
across this problem occasionally and is spotted by a huge amount of
vibration just as you are releasing the clutch and moving off from a
Hope this is helpful to you.
Joint DB18 Registrar (DLOC)
(Also an ardent SP250 owner)----- Original Message -----
From: Payton Fireman firstname.lastname@example.org
To: Daimlan @ jaglovers.org email@example.com
Sent: Monday, April 24, 2000 12:25 AM
Subject: [DaimLan] C Spec Rear End
Speaking of late production modifications to the SP250:
I recently told by John Carey of Ipswich, Mass that a late production
modification to C spec SP250’s was the installation of a slightly
rear end. The pinion bearings were positioned 3/4 inch wider apart in the
housing to give a longer bearing radius to the spider gears, etc.
This was done to address weakness in the early rear end that was not
enough for the drive train. One can identify the later rear ends by
at the top of the rear end housing. The early rear ends had a fill plug
the very top of the rear end in addition to the one in the middle of the
housing and the drain plug on the bottom. The late model rear ends had
Can anyone confirm this? My C spec does only have two plugs, top and
middle. Anyone out there willing to crawl under the car to see if they
a top plug?
Morgantown, West Virginia