Full sized spare in MD Wagon.

[AlanD]

Hi to all.

After 5 years I have finally done something about a full sized spare wheel in the Mondeo Wagon.

So I thought I would share the experience if there are others who might want to do the same. The attached photos show the under cargo floor mods and the finished result.

The discoveries:

1. The cargo floor in our car is not horizontal, it slopes down towards the tailgate and the polystyrene “fillers” are tapered (thicker at the front edge.)
2. The six fasteners (three in each side) in the track strips are M8x25mm Torx drive (T30) bolts and they are thread locked, you will need an appropriate wrench to extract them.
3. You will end with the back edge of the floor raised slightly above the chrome scuff plate, which you can see in the photo. This is because if you use the tyre size I have the side nearest the back of the car is slightly proud of the original floor level.
4. The handle in the floor needs to be removed and the resulting hole filled with a cover plate. This is because a part of the handle assembly protrudes below the floor and fouls the wheel hub area. But because the back edge is raised this is not a major concern as it is easy to lift the floor from the back edge that is not recessed as it was earlier.

The things you will have to source:

1. Some longer M8 bolts. I sourced some “Pinnacle” bolts from Bunnings in 35mm and 50 mm lengths. They are 5mm hex drive and I replaced all six so I will not have to mess about with different bits in the event I want to remove them.
2. Two M10 couplers (Bunnings sell them, galvanised in packs of 4)
3. A 30mm M10 grub screw and a 60 mm M10 grub screw (These I sourced from a supplier via eBay but any good fastener supplier could provide them.)
4. Two pieces of material (wood?) measuring 50x18x100
5. A lath of wood measuring 50mmx8mmx1020mm
6. A 17x7 5x108 wheel. Such wheels were fitted to Ford Focus, Volvo and Jaguar cars, there may be others, with at least a 45mm positive offset but not more than 55mm. As there wasn't much difference in cost from a second hand suitable wheel, I bought a CSA Milan wheel in the stated size that pattern matches the road wheels I have on our car.
7. A 205/55R17- 95W Tyre. Since this tyre will not see the road often I bought the lowest cost item the wheel supplier could get which turned out to be a Farroad item at $110. 95W gives a load rating of 690 kgm and a speed rating of 270kph or about twice the car's capability. The OE tyre spec is 98Y or 750 kgm and 300kph but I note from the tyre placard on the vehicle the diesel engined car can have a tyre spec as low as 96W ie 710 kgm. I guess leave the tyre on the car for as little time as is reasonable in the prevailing circumstance of use.

I have discovered that a company called Nankang produces a tyre in the 195/60R17 size that would allow the finished floor to be 10mm lower and such a tyre has a free diameter only 3mm smaller than the OE tyre – but it has a 90H rating and that is getting rather too far away from the OE spec for me to consider it.

What I think is the speediest way of proceeding, based on my experience.

1. Remove all the junk that has accumulated in the cargo area – if you don't have any then kudos to you. Remove the filler piece above the spare wheel. Release the spacesaver wheel and tyre and remove it. Put both items out of the way.
2. Lift out the floor panel and put it out of the way. It is secured towards its front edge with two plastic hooks mating with pins attached to the polystyrene filler. With the floor close to level pull backwards to disengage them then lift.
3. Unbolt and remove the fence runner tracks.
4. Lay the lath across the car sitting on the centre pair of holes and mark on the edge of the lath the bolt hole positions. Carry these marks onto the wide face of the lath and mark in the middle. Drill right through with a 10mm drill.
5. Position the 50x18x100 spacers over the rear most bolt holes such that they clear the filler and mark a hole position (see one of the attached pics). Drill a 10mm hole at this position in each piece.
6. Place the lath across the car aligning with the centre bolt holes.
7. Replace the fence runners and loosely bolt down at the forward pair of holes so that towards the rear the runners can be raised. Use 35mm Pinnacle bolts – take care the thread lock makes it easy to cross thread these fasteners.
8. Align the 50x18x100 spacers with the bolt holes at the rear pair such that they overhang towards the centreline of the car.
9. Insert 35 mm bolts in the centre pair of holes through the lath and use 50 mm bolts to do the same through the spacer pieces.
10. Tighten all six bolts, if you want a torque figure I'd suggest 30Nm would be appropriate.
11. Take one of the couplers and screw in the 30mm grub screw to half its length. Run the open end of the coupler down the tie down screw until it bottoms. With a suitable OE spanner on the coupler use a suitable allen key to cinch up the grub screw. Run the second coupler down the exposed end of the grub screw until it bottoms and then cinch the two couplers with a pair of suitable spanners. Run the 60mm grub screw into the open end of the top coupler and cinch it as described previously. In my case the extended tie down rod was just the right length to allow the plastic hold down “nut” to engage the full thread of the nut with no overhang. This is ideal.
12. Put your “full sized” spare into the well and secure it. Well done, but not quite finished ---
13. Retrieve the floor and remove the lift handle (two small torx headed screws T20). To make a blanking plate I sacrificed a black single CD/DVD case which has a plain front face. Scribe an outline on this face using the top half of the handle as a template and cut this shape out. I used some poultry shears, but suspect tin snips would be better. Secure this onto the floor surface. I used some 12mm self tapping pan head screws but double sided tape would do as well I suspect.
14. Replace the floor by dropping its front edge suc that the hooks are behind the pins of the under floor filler then push forward until they engage and the floor rear edge aligns with the rear end of the fence runners. – you are all done – Congratulations.

Final comments: This got precipitated by a combination of the car needing new tyres and I decided that it might look good with black rather than silver wheels so the CSA Milans got purchased as well. And I have been grappling with the absence of a full sized spare whenever we travel, which is reasonably often, in fact next week is the next excursion. Also we have some plans for a big road trip to FNQ from Melbourne going inland rather than Highway 1 where centres of civilisation can be longish distances apart – being restricted to 80 kph for a limited distance isn't useful in Australia and that spacesaver is a lot smaller than the road wheels. The new spare has a radius which is 5.5mm smaller than the road wheels or atread depth if you like – I can live with that sort of difference.

The space saver and the polystyrene insert should be safely stored, as should the floor handle – you might want to return the car to “as delivered” condition at some point in the future.

I'm happy for this to become a “sticky” if that is felt to be worthwhile.