What's everyone's thoughts on plugging the frame rail holes?
- Thread starter kzrider
- Start date
vito2772
TJ Enthusiast
vito2772
TJ Enthusiast
I'm guess to stop mud and other gunk from getting shot up into the big hole above the rear axle in the frame on both sides.
I agree, I don’t see any harm in it. As recommended though, I would spend some serious time ensuring the inside of the frame is clean. What are you planning to use to close it up?
The entire frame has a ton of holes. You are better off just drilling proper drain holes.
LONGJP2
TJ Expert
If you're talking about the four (large) holes that you can buy plugs for, then no problem. It should reduce the amount of stuff that gets inside. Obviously not a cure all.
If it never sees salt or slush.
FWIW, I've used the Fluid Film in the fall all three years that I've owned mine so far and I drilled the drain holes the first year. Last fall I went one step farther and covered every hole on the top and outside of both frame rails with Gorilla tape. It's been 3 months now, the tape is still there and I'll be surprised to find anything in there this spring that wasn't there when I closed it up in early November.
I think everyone who owns a TJ should plug the large holes in the outer frame rail. It doesn't matter where you drive, the tires WILL throw debris into the frame through those holes and when that debris (sand, mud, salt...) mixes with water the moisture will be trapped.
There is no downside to frame plugs. I've seen some argue that they'll trap water, but for every hole in the outer frame rail there is also a corresponding hole in the inner frame rail. I installed them when my '05 LJ came to Minnesota in 2012. The inside of the frame is still dry and perfectly clean.
There is no downside to frame plugs. I've seen some argue that they'll trap water, but for every hole in the outer frame rail there is also a corresponding hole in the inner frame rail. I installed them when my '05 LJ came to Minnesota in 2012. The inside of the frame is still dry and perfectly clean.
My understanding was that the frame holes are crumple zones to keep you somewhat alive in the event of a collision. Is that not the case?
The 4 large holes by the tires are access holes for the upper control arm bolts.
I use those and others to hose out the frame with a pressure washer every few weeks when the Jeep gets washed.
Thanks all. I bought plugs from Amazon. Pressure washed the heck out of the frame till nothing but clear water ran out. At least they’re removable so I can flush from time to time. I’ll also check out “Fluid Film”
Thanks all. I bought removable rubber plugs off Amazon. Flushed the frame rails till clear water came out. Going to check out “Fluid Film” as well. I have a 97 with a very clean undercarriage/ frame and want to do my best to keep it that way. Might try Gorilla tape as well on the smaller holes.
I think the only crumple zone holes are the 4 or 5 in a row on the top edge of the frame just behind the grille. They may be on both sides of the top, if so I still only taped over the outboard ones.
Any time you can prevent shit from entering the inside of the frame it is a good thing. But you also need enough ventilation in other areas to keep the inside dry. If you were to completely plug up the frame then any moisture that finds a way in will let rust consume the metal. So those 4 holes that allow mud and salty slush from the tires in the frame are a good idea to plug. If you live in some place like Arizona I see little benefit, if you live in the salt belt then good idea. If you are mud bogging good idea. But be sure to have drain holes. And those plugs only really stop the big stuff. Keeping them removable is a good idea for frame inspection. There is no perfect answer for all vehicles. User discretion applies here.
