Monarch BMW Differential Conversion Kit for the Stag

This kit comprises a pair of Stag rear subframe arms welded to a suitable BMW diff cage, a modified Stag diff mounting bracket, two diff flange adapter spacers to mate up to your Stag drive shafts and a brand new GKN propshaft supplied to the correct length. The whole assembly is set up in a jig and as the Stag subframe arms are welded to the diff cage (the original is bolted and the bolt holes wear oval allowing play and hence misalignment of the rear suspension geoetry), there is a huge improvement in handling and it usually cures rear wheel camber problems as well.

To fit, remove your exhaust rear pipes from behind the silencers, disconnect brakes & drop your old subframe out (4 fixing points). Transfer the trailing arm brackets complete with trailing arms and hubs to the new unit. I suggest that this is the moment to fit our Superflex polyurethane bushes. You will not regret it. Bolt up the new unit to the car. Don't forget to send me your two subframe arms and rear mounting bracket in exchange or I will have to retain the exchange surcharge. Your units must be clean and in good rust-free condition.

To take care of big, powerful Rover conversions producing more than 200BHP the price includes my uprated bigger diameter (3.5") propshaft with heavy duty U/J bearings to handle the extra power and be sure there is no vibration at very high speed.

Ratios available: 2.93/3.07/3.25/3.46/3.71
Only your subframe arms & diff mounting plate are required in part exchange, not the Stag diff.
I can also provide a limited slip diff for a little extra cost, subject to availability.

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