Found rust on mine there too. Hit it with a wire wheel and went through the frame 
Check your skid plate, it is probably rusty
- Thread starter Johnfromphilly
- Start date
OP
It was a great project. Saved long term damage and now I know what is going on under there. Learned some new stuff along the way too.
OP
Thanks, I cannot take credit as it was recommended to me by @Chris when I bought my TJ and asked what I should do for maintenance. I posted the thread because it really surprised me how much rust there was on an otherwise perfect frame.
OP
I decided not to do this, it was suggested by a few folks. Frame and skid plate are clean of rust, primed and painted. I also added oil based lubricant between them prior to reassembly. I also plan on checking it again every so often. I am trying to keep things as stock as possible and when I looked at the indentation on the skid plate it would have taken a bunch of washers to separate the two. It would mean the transmission was dropped and I just didn’t want to mess with the look of the Jeep or mechanics of the transmission.
OP
Just an FYI for Jeep owners that can't keep their Jeeps inside. I found my skid similar to the OP's. I cleaned, primed and painted, like the OP. A year later, when I removed the skid for my SYE, I had to clean, prime and paint again.
I believe in certain conditions or areas of the country, skid maintenance is a yearly job. I coat my undercarriage twice per year with Fluid Film, and my frame looks fine.
I believe in certain conditions or areas of the country, skid maintenance is a yearly job. I coat my undercarriage twice per year with Fluid Film, and my frame looks fine.
Yes, the transfer case. That is unless you have a crossmember, which would be all aftermarket so you’d likely know.
Before you cut them off, try soaking them with PB Blaster for a week or so. Then take an air gun to them a just blip each one a couple of time like your tightening the bolt. This will compress the nut zerk so they won't spin.
Then attempt to loosen them.
If the PB doesn't do it, mixture of tranny fluid and acetone for the next week or so may succeed. Kroil would be an even better try.
No matter what kind of nuts, tightening before loosening is definitely the way to start. I wish I was born with that knowledge but at least I learned it fairly early. Sometimes you can get away without oil first but I wouldn't try these without oil.
FWIW, I had to look up "nut zerk". Based on google, that may not be a term but they gave me so many pages of nutserts I figure "nut zerk" was a typical result of "talk to text".
I actually just got mine all finished the other day. I had a transfer case drop from the previous owner which for some reason used Allen bolts that got so rounded I couldn't get any torque on them at all.
I plan on installing my body lift soon so I am going to keep spraying all the bolts every now and then, I have some of the atf/acetone mix that I've been using so I hope it works. I am really worried about snapping those bolts because I don't want to have to cut an access hole, I think I'll try the tightening a little bit ahead of time method. Would it be better to use an impact or a long breaker bar on those? (for both tightening at first and removing) I
Inspired to check condition of my skid plate. What is required to remove skid? Support tranny an tc, after skid removal. Appreciate some advice.
initially I too was adding lubricant (fluid film in my case) between the skid & rails, but in time I realized it was attracting enough dirt & debris from off road and that it all eventually combined to became an abrasive which grinded on things, not good; despite the fact that the skid appears static, the frame does move & flex enough to present issues.
I abandoned that regimen in favor of adding just one washer to each bolt as a very thin spacer between the skid & rails which is enough to separate these pieces AND for great air circulation; despite that indentation on the skid the protrusion of the nutsert on the frame side fills it enough that the addition of one washer allows me to see a space between the two, a condition lacking in the original design which explains why these areas are rusted even in non-rustbelt states... if you trap water between two pieces of iron it'll rust anywhere, eventually.
On my rig it's a small thing, barely noticeable, but something I believe will go a great distance towards slowing or eliminating the issue caused by this design.
I just use a Jack under the transmission and then a couple of jack stands once the skid is off.
I did my frame from the front arms back last year, I was too nervous to remove skid plate. When I had my tcase drop removed last month I asked the shop if the bolts put up a fight and they had no issues. Maybe it’s cause I soaked them for 2 weeks straight last year 
. I had the shop grind the frame and paint it where the skid meets while they were in there. I still need to do the front 1/3, but it’s in great shape.
. I had the shop grind the frame and paint it where the skid meets while they were in there. I still need to do the front 1/3, but it’s in great shape.I usually pack the area where the steel goes directly against steel with chassis grease before assembling.
One of the first things I did to my last 3 Rubicons was remove the rocker skids, coat the inside liberally with grease, reassemble and wipe off any the oozed out. Same thing with the windshield hinges
One of the first things I did to my last 3 Rubicons was remove the rocker skids, coat the inside liberally with grease, reassemble and wipe off any the oozed out. Same thing with the windshield hinges