Need to replace a blowing rear silencer? Want to upgrade to a performance exhaust like the popular 6x4" Janspeed Oval?

Follow this step by step guide to removing and replacing the exhaust backbox on your MG ZR / Rover 25.


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Time to Complete - 30 minutes


Difficulty - 3/5


Tools and Parts Required




Disclaimer: Any information given in this guide is to be used at the readers own risk. I take no responsibility for injuries to the reader or damage to their vehicles. If this guide is followed correctly, no harm should occur to either the reader or the car.

Please read through the entirety of this guide prior to undertaking any work, and take due care.



How to remove and refit a Rover 25 and MG ZR Exhaust Backbox


Step 1 - Jack up the Car

The first thing you will need to do is get the car off the ground giving enough access to the backbox. You might have access to a hydraulic lift, but for the majority of us we don't. So chock the front wheels (put a block of wood in front of the front wheels) and start jacking up the rear of the car. The car should also be in reverse gear.

Step 2 - Spray Bolts with Penetrating Oil

Once suitably elevated locate the join between the backbox and intermediate pipe, starting from the back of the car this is the first set of flanges you come to. In the image below you can see the join in my car, please note however that I have an exhaust extension, you will only have one set of flanges not two. If the backbox has never been removed, or at least not in a long time, it'd be worth spraying a bit of Penetrating Oil on the bolts prior to trying to undo them.

MG Rover 25 Backbox flange

Step 3 - Undo Bolts

Using the two 17mm spanners (in opposite rotations) undo the two bolts holding the gaskets together.

17mm Spanner



Step 4 - Unhook Exhaust from Rubber Hangers

The backbox should now be free of the other sections of the exhaust. The only thing holding it on now are the two rubber bushes at the box end of the backbox and one half way along the piping. To get the backbox free of these simply push the rods out of them. The backbox should now be completely free of the car.



Step 5 - Remove Exhaust

Getting the backbox away from the car requires a bit of angling and tilting to get it passed the rear axle, but should be fairly easy. When removed the backbox should look similar to either of these, the top being the original rover backbox and the bottom being a custom Longlife stainless steel oval tip backbox.

MG ZR Rover 25 Backbox

Step 6 - Refit Exhaust Backbox

Refitting is a case of reversing steps 1 - 5. However, it is good practice to replace the gaskets when you replace or remove and refit an exhaust component. Also a helpful tip for getting the rods back into the rubber bushes is to put a bit of washing up liquid on them, they should then slide in quite easily. Whilst the car is still jacked up, (disengage reverse gear) start the car and check for any blowing in the exhaust and at the flanges.