Kilby skid plates + diff drop?

[BigSwede]

Has anybody installed their Kilby skids yet? I haven't noticed any chatter since the group buy.

More specifically, has anybody with a diff drop installed Kilby skids? I was looking under the Trooper yesterday, and it sure seems like significant modification will be needed to make it work with a diff drop. It looks like the replacement crossmember will pass right through the dropped front driveshaft. This is important, since the skid plates attach to that crossmember. And the diff pumpkin looks pretty low too.

[VX KAT]

I got mine installed, but I don't have diff drop.
Here's pics, maybe it will help you, but I know you have a Trooper.
Pics start at post #128
http://www.vehicross.info/forums/showthread.php?t=16573&page=4&highlight=kilby+skid

[tom4bren]

See post #140 here:

http://www.vehicross.info/forums/showthread.php?t=16573&highlight=Kilby

As far as the diff drop:

I've got a set of brackets to lower the new crossmember to clear the diff but that'll only be part of your problem. Lemme know.

If you drop the crossmember then the angle of the plate will be wrong for the mounting holes to line up. You may be able to get away with this with just some longer bolts. If not, you should be able to get the plates modified at a machine shop in your area.

Short short shortier short cut to post #140 (see Ldubs post below):

http://www.vehicross.info/forums/showpost.php?p=189480&postcount=140

KAT - when you find the post in a particular thread that you want to direct someone to - click on the post number and it opens up that post in a new window. Copy that url to the thread you're referencing from. (Just a Handee little tidbit of info for future reference).

[Ldub]

I got mine installed, but I don't have diff drop.
Here's pics, maybe it will help you, but I know you have a Trooper.
Pics start at post #128
http://www.vehicross.info/forums/showthread.php?t=16573&page=4&highlight=kilby+skid

Here's a short short shortier short cut, directly to post 128...:smilewink

http://www.vehicross.info/forums/showpost.php?p=181832&postcount=128

[VX KAT]

KAT - when you find the post in a particular thread that you want to direct someone to - click on the post number and it opens up that post in a new window. Copy that url to the thread you're referencing from. (Just a Handee little tidbit of info for future reference).

TANKS T4B....I've done that before, but musta not had enuf java juice yet dis mornin'....not firin' on all 3 brain cells yet!

[BigSwede]

Thanks guys, I lost track of that thread. The skids look very nice and should work well.

Though you might want to invest in a set of Irwin Bolt Grip extractors for deformed bolt heads...or maybe if you can find something like an allen head carriage style bolt, those would be a lot less likely to catch on rocks and such.

Getting back to my original point, with the diff drop I am quite sure the crossmember will have to be substantially modified. By eyeball, it looks like the crossmember and diff pinion intersect almost exactly. I am actually thinking it might be best to bridge the crossmember over the driveshaft/diff pinion instead of under it, but a test fitting will be necessary to really judge that.

And, the diff pumpkin will almost certainly intersect the front angled plate. A clearance hole will have to be cut, and maybe a bridge built over the hole to protect the pumpkin.

But I was hoping somebody had done all this already and could tell me exactly what is needed...:smilewink

At any rate, I am looking forward to laying on the driveway of the Red Rock (intentionally) pretty soon and looking at some skids. :happyface

[tom4bren]

I'll look tonight on mine to see how much clearance between my diff & crossmember. Your new crossmember from Kilby looks very much like the Calmini crossmember on mine. I'm assuming that it's from Calmini because the PO installed their lift kit. I didn't even know mine was aftermarket till I helped someone else with their diff drop installation.

[BigSwede]

Did the Calmini kit include a diff drop? I wasn't aware of that, but there would be little reason to replace the crossmember otherwise.

[tom4bren]

Nope, diff drop NOT included with Calmini lift. I don't know why they provided a new crossmember.

I just checked & I have less than 0.5 inch clearance between my differential and the crossmember. IIRC we made the diff drops 3 inches & the crossmember drop 1.5 inches.

Tom

[Ldub]

Getting back to my original point, with the diff drop I am quite sure the crossmember will have to be substantially modified. By eyeball, it looks like the crossmember and diff pinion intersect almost exactly. I am actually thinking it might be best to bridge the crossmember over the driveshaft/diff pinion instead of under it, but a test fitting will be necessary to really judge that.


How bout cross cutting the Kilby plate where it intersects the cross member, welding mounting tabs to both sides of the cross member, L & R with a nut welded on top, drill holes in the cut Kilby plate that line up with the new mounting tabs, then bolt it up from the bottom...:_wrench:

[BigSwede]

Not sure if it has enough depth for that...in any case such fine details will have to be sussed out AFTER Moab...

[tom4bren]

I'm thinking that the Kilby plate is strong enough to use as the crossmember. Just remove the stock crossmember and modify the crossmember drop brackets for something to bolt the back of the 1st Kilby plate & the front of the 2nd Kilby plate to.

[BigSwede]

That might be worth looking into...I remember Jerry Lemond telling me that the crossmember there doesn't do much of anything, and he wasn't even sure it is needed!

But I do hit rocks pretty hard on occasion, so I think something backing that plate joint would be a good idea.

[tom4bren]

UH-OH! I'm thinking again ...

If you do eliminate the crossmember & just use the Kilby plate, you can gusset the seam between the 2 plates with a tapered plate mounted on the down side of the plates. Sorta like a threshold plate for the front door, but much thicker material.

The first step though is to find out if the Kilby interferes with the differential.

[Riff Raff]

http://www.vehicross.info/forums/showpost.php?p=193534&postcount=155 Hmmm, perhaps Post #155 may be a better source for specific information.:bgwb:

[RamAirZ]

Not specific about a diff drop though, which is the original question.

[Lucian08]

So with VX Kat's Kilby plates up for sale I wanted to see if anyone has thought about this old thread anymore. Will a diff drop fit with the Kilby plates? The answer looks like 'No', but how difficult would it really be to modify the plates? I have the Darlington diff drop sitting in my garage and no kilby plates so I don't have much to compare. Anyone?

[BigSwede]

I never did install the skids, sold them instead (not because of this issue, but because I was getting out of hardcore rock crawling in general).

[tom4bren]

I would think that it shouldn't be too difficult. Just bolt it front & back, then add spacers (washers) between the plate & frame to all of the other bolt holes. You may need longer bolts for the ones closest to the crossmember.

[VXorado]

I installed the kilbys with a 2" diff drop successfully. All I did was drop the crossmember 2" with some homemade brackets and all of the plates fit correctly.

The other option is welding brackets directly on the skid plate and deleting the crossmember. This option gives you more ground clearance but you lose strength without the crossmember.

[tom4bren]

That would work too. The skid plate would actually be your crossmember.

If you go that route though, I'd suggest a plate with a chamfered leading edge to cover the seam between the front & rear plates.

[VXorado]

That would work too. The skid plate would actually be your crossmember.

If you go that route though, I'd suggest a plate with a chamfered leading edge to cover the seam between the front & rear plates.

Yeah you do lose a bit of strength though. I've tweaked the center skid plate now that it rubs on the front drive shaft CV and makes a terrible noise. I dealt with that issue in Moab and haven't put the skid plate back on since. It would be a good idea to add some cross sectional strength to the skid plate for anyone using it as a cross member. :thumbup: