C5 X7 undertrays, is there a gap or a bridging piece?

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Jay-Bruce
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C5 X7 undertrays, is there a gap or a bridging piece?

Post by Jay-Bruce »

I've just started fitting a new front undertray, and when I offer it up to somewhere that looks about right, holes in the tray match up to fasteners on the body, there's a 8" gap between the back of the wings of the main engine undertray, and the first of the undertrays that runs between the sill and the exhaust tunnel. So I'm wondering if the copy cat part off eBay is badly made, or if I'm missing more pieces of undertray? Is anybody able to provide me with some diagrams and or photos of the undertray arrangement so I can see whats going on?
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GiveMeABreak
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Re: C5 X7 undertrays, is there a gap or a bridging piece?

Post by GiveMeABreak »

These are all the underbody protection parts Jay - note the bottom right diagram of the entire vehicle with parts shown assembled.
jay under.PNG
Let me know if you need part numbers for any items.

Yes, pattern parts can be horrendously badly fitting. I ordered the main underbody shield for my MK II C5 supposedly a Polish copy part and it was totally useless and would never fit using their holes. We had to drill our own, suffice it to say 3 months later...... it went to the great undershield place in the sky via way of the dual carriageway. Never again.
Please Don't PM Me For Technical Help

Marc
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MattBLancs
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Re: C5 X7 undertrays, is there a gap or a bridging piece?

Post by MattBLancs »

This gap?
From Marc's diagram
From Marc's diagram
Similar gap on mine (aftermarket under engine tray, standard two further back) leaves a handy length of subframe steel bracket exposed - with a piece of wood that's where I put the jack (axle stands then under the standard points on the sills)

Aftermarket under tray is ok, fairly thick plastic. Drilled a hole under the sump drain plug position to reduce number of times I'll have to shift it.

Mine is installed with M6 bolts, penny washers and Nyloc nuts = not going anywhere. Never like using the PSA body spring clips and large headed "screw that's not a screw" things so tend to replace them whenever I encounter them!
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MattBLancs
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Re: C5 X7 undertrays, is there a gap or a bridging piece?

Post by MattBLancs »

Couldn't remember what far flung place mine came from so just dug into eBay history. £45 Inc delivery. Somewhat less far flung that my memory suggested!
Spoiler: show
eBay says: "item location: Peterborough" :-D
Jay-Bruce
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Re: C5 X7 undertrays, is there a gap or a bridging piece?

Post by Jay-Bruce »

After looking at the picture on the eBay listing, and the diagram above, tt looks like the OE one stops in the same place as the copycat one I've got, going by the location of the last bolt holes etc. I really don't like the idea of a gap like that in the trays, especially as it leaves some fuel, brake & suspension lines exposed, so I guess I'm going to have to McGuiver up something to bridge the gap to shield those pipes. Matt, I think we have the same item, £45.89 from Peterborough - https://www.ebay.co.uk/itm/322843733787
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MattBLancs
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Re: C5 X7 undertrays, is there a gap or a bridging piece?

Post by MattBLancs »

Yes, that's the one I bought. Seems ok to me, certainly for the money.

I'd forgotten another piece of hardware involved in the installation on mine - the two round aluminium tubes (running along the car either side) standard holes ignored completely (one per side) and tubes drilled for M6 rivnuts. (Undertray also drilled, clearance holes) two per side.

Towards the back there's a single fixing on each "wing"
I drilled and tapped an M6 threaded hole for one extra fixing per wing. Tended to droop a little away from the fixing as intended, hence adding extra.

I've used cheap mild steel bolts and washers, copper greased very liberally. Will see if that was enough next time I've to take it off!
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bobins
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Re: C5 X7 undertrays, is there a gap or a bridging piece?

Post by bobins »

Here's what Citroen intended it to look like when fitted :)
C5 X7 Undertray - Citroen / PSA / Stellantis / AN Other
C5 X7 Undertray - Citroen / PSA / Stellantis / AN Other
Sadly no longer a C5 owner :(
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Re: C5 X7 undertrays, is there a gap or a bridging piece?

Post by MattBLancs »

Red X= additional fixings (front four = rivnuts. Other two = tapped hole in subframe)
Orange circle= standard fixings ignored
Crude mark up
Crude mark up
Jay-Bruce
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Re: C5 X7 undertrays, is there a gap or a bridging piece?

Post by Jay-Bruce »

Cheers fellas, I'm hoping to get on it tonight, assuming I don't drown today on my sailing course :rofl2: