RCI skids popping/cracking sound? UPDATE - *FIXED*

I'm curious if anyone else running RCI skids, or combination skids from another company have ever had them pop or crack when turning/articulating. My guess is it's rubbing under pressure where the transmission skid mates up to the engine/diff skid, but I have the bolts torqued to proper setting. Maybe I'm overthinking this but would simply spraying a little Fluid Film or something inbetween the skids lube it enough to allow them to move?

 

I have a bunch of skids but not all of them. Never had an issue.

Don't have (yet) trans, xfer case. Probably won't get LCA skids; not big on the idea of plugging their water drain holes to use as mounting points. They're steel and probably rub over rocks OEM fine, and can also be welded.

If this was my truck I'd have numerous thoughts.
#1: it would take more diagnostic work to figure out exactly where the noise is coming from/what's causing it
#2: would be under the impression a $50 factory part subjected to age, miles, and off roading has worn out somewhere, exhibiting issue, such as LBJ's, etc.

certain skids installed them, don't think I used a torque wrench. ie gas tank
others have come off and on again many times, also no tq wrench, like engine skid for oil changes

finding the source can be tricky. I've had a clunk be from steering rack bolts. A squeak from one LBJ needing grease. The sound would spread so much it was still hard to determine even laying under the truck rocking it up and down to hear.
Ended up using best guess, process of elimination, etc.

 

Maybe it's a possibility that I shouldn't have torqued them down and that's what is causing them to do this? I just went by factory specifications, but having these skids on isn't factory anymore. I'll try loosening the bolts a little bit to see if that helps. It definitely is coming from the skids because it didn't start doing this until I installed them.

 

Haven't run into it with the big skids, but the TRD skid is famous for making noise.

What I do is grease the contact points (plate to x-member) with antiseize, so if it wants to shift it can do it quietly.

 

IDK what would be different about the torque, if they go into original holes
my engine skid doesn't, it came with aftermarket retainer threads
I went by feel, so did installer

unless they have a torque spec. Sometimes companies do on their website for various parts.
Or they usually say at least recheck after 100mi.
I know I rechecked hardware on my RCI sliders but forget if it was to an actual torque spec or just feel again.
Roof rack for sure has a tq spec on the mounts as they're pretty sensitive.

I mean, it could be a coincidence,
or it could be the cause, 50/50
another way to know is take them off, see if it stops

I'd assume they're on there tight enough and not moving. Which makes me wonder if something else is moving and possibly hitting them. Like even certain stock parts have a little bit of movement naturally, like exhaust, engine (on OEM motor mounts), etc.

for my engine skid I usually get it up, thread in all the bolts by hand, with my hands try to get the skid sitting evenly, then go around in increments wrenching all the bolts down until they're tight around the same time. Sometimes wire brush clean. Could be overkill, some people just impact them real quick.

 

I'm going to get under there tomorrow and have a closer look when i have more time. I really think it's where the transmission skid overlaps over the engine skid. The only thing I can akin this to is plates of the earth popping when they move over one another. This is what it sounds like more than something hitting it. I'll loosen the two bolts holding the two skids together and spray some Fluid Film inbetween them to see if that helps. Thanks for the replies.

 

you could contact the skid maker

I know for mine I've got basically two different brands so they're probably gonna need custom fabwork/at least trimming to make the trans skid fit the engine skid
as right now holding them up together, not only would they stack and prevent good tightening of the trans skid, but trans skid would sit lower than engine skid which is bad as that would make it likelier to snag

I'm gonna have to figure out if that's easy "custom" work to resolve, like cut myself, or maybe measure, mark, and take to a machine shop for work.

Did something similar to make WarFab tie rod sleeves fit my aftermarket tie rods of a different diameter. Took to a machine shop to have the sleeves bored out a bit, ended up being around $20 I think. Maybe a bit more.

 

I think I was right about the skids rubbing together. I sprayed some Fluid Film at the connection where they meet together as well as all the other contact points to the truck. I drove to work this evening and didn't get one pop sound. Maybe it just needed a little bit of lubricant between the metal surfaces.

 

Quick update, I removed the bolts holding the rear of the engine skid and the front of the transmission skid and placed a fender washer in between the two skid plates. Tightened everything back up and took it for a ride. No noise. I would like to clarify that I don't think this is the fault of RCI because when I took one of the bolts off from the rear of the transmission skid, I had put what appeared to be an extra washer on that side which I believe was supposed to go up front. Anyway, the two skids were obviously binding up when the truck flexed a little on turns so the washer fixed the problem.

 

I have full RCI aluminum skids on my 3rd gen and had an atrocious creaking/popping/clunking noise at low speeds and while turning. I assessed everything that I could think of and couldn't find an issue (no loose bolts, wasn't the body mounts, not UCA uniballs, not wheel bearings, etc). I was already replacing my coilovers and rebuilding my UCAs and the noise still persisted afterwards.

I finally figured out that it was the aluminum skids where they meet (engine skid to transmission skid and transmission skid to transfer case skid). I removed the bolts at these two intersections and added thick rubber washers in-between them and made sure I didn't overtighten the bolts and now the truck is silent!

It's M8 bolts at engine skid to transmission skid and 3/8" bolts at transmission skid to transfer case skid (at least on my 3rd gen). I used 1-1/2" OD x 3/8" ID x 1/8" thick rubber washers at both locations and no more noise (thank god )

What I used:

$6 Rubber Washers - 16PCS Flat Rubber Washers for Bolts Spacers, 1 1/2" OD x 3/8"ID x 1/8" Thickness, Heavy Duty Abrasion Resistant Rubber, Black Vibration Damping Pads

https://www.amazon.com/dp/B0BJPBRQJQ

 

Nice! Even after I moved the washers around, I was still getting a popping sound when turning. I took my truck to a buddy's shop and had him look at it. We removed the transmission skid and the popping stopped. It turns out that when I put the transmission skid on, I didn't loosen the front 4 bolts on the differential skid first, so the transmission skid was slightly off from the front. Both skids were removed and reinstalled at the same time and with more washers and I haven't had a problem since. My suggestion to anyone else having this problem is to finger tighten everything first until all skids are in place. Then tighten it all down with washers in between.

 

On my 3rd gen there are spacers that go between skid and xmember where the eng./trans. meet up.
RCI has an installation order and torque specs for the skids on their website.
For the bolts, I didn't use a torque wrench.....it's a skid plate.

I get a little chirp every now and then. Pretty sure it's from the exhaust because the cat guard is almost, if not, touching the driver side cat.

 

Thank you! I've taken my skids off multiple times and added washers, reinstalled, and torque spec'd and it would come back time and time again. I was about to pull the trigger on some c4 skids since they are 2 pc but I think I'll give this another shot. Does anyone have any suggestions for the god-awful rear skid crossbrace to keep it from moving? Did anyone drill into their frame to add more bolts or anything? Just curious.