Jeep Enthusiast Forums banner

Drilling holes in the Frame, in order to drain

17K views 77 replies 29 participants last post by  GreenliftedTJ97 
#1 ·
Gentlemen,

Been reading mixed information whether this a good idea or not. Basically I am noticing that the LJ when parked on a slight incline lets quite a bit of water come out of it from the passenger side where the lower control arm is. Almost nothing on the drivers side.

Some say to drill an additional 4 holes to let it drain out. My question, is this really worthwhile? My Jeep is not winter driven (sees no salt), I try to keep it out of the rain as well.

I plan on spraying some eastwood internal coat frame here in the next few weeks to preserve the frame as long as I can.

So reading all these mixed reviews some say it weakens the frame by drilling the holes and some say no it doesn't. What's the common verdict here? Most of the reviews I read where actually from other boards. And if so, where exactly would one drill these holes?
 
#2 ·
I did mine, one hole couple inches from each of the the 4 control arm mounts. I'm here in north Texas with little snow/ice/salt but still seemed like a good idea.

3/8-1/2" holes I don't think will weaken the frame as much a rust. Spray painted homes good to reduce rust on bare metal. Amazing how much crud came out, and I always washed my frame rails out at least a couple times a year.
 
#3 ·
I did mine, one hole couple inches from each of the the 4 control arm mounts. I'm here in north Texas with little snow/ice/salt but still seemed like a good idea.

3/8-1/2" holes I don't think will weaken the frame as much a rust. Spray painted homes good to reduce rust on bare metal. Amazing how much crud came out, and I always washed my frame rails out at least a couple times a year.
So what did you do afterwards when you drilled the holes? Since its bare metal at that point.
 
#5 ·
The FSM states not to drill any holes within 1" of the bottom of the frame. If you were going to do it though I would weld a washer around the hole but looking at the chunkiness of the mud around here it would just get clogged anyways. What I did instead is make a flexible hose similar to a better that they use for breaking up clogged plumbing that I can feed into the frame to break up the dirt so it will float out.
 
#6 ·
The FSM states not to drill any holes within 1" of the bottom of the frame.
Wow, this is why I'm checking the forum all the time. I was going to drill some holes, because it didn't occur to me that I should check the FSM.
 
  • Like
Reactions: Eric Mowrer
#18 ·
I drilled my holes right through that hole in the rear lower control arm bracket. And then sprayed the Eastwood product inside the frame, it coated the freshly drilled hole nicely. Seeing the pics of the guys with rotted out frames still wheeling their rigs gave me piece of mind that my new little holes weren't going to cause any problems if their frames could be missing several inches of rot.
 
#19 ·
My frame was full of sand and mud and it seemed that no amount of flushing was getting everything out. I would get a few particles here and there out of the holes in the side, but no where near everything. I drilled a 1/2" hole just in front of each rear control arm and within two flushes the entire frame was cleaned out.
 
#20 ·
Regarding what the FSM stated, assuming their concern would be drilled holes would weaken the frame, I would think that holes in the sides, or verticals, would make the frame weaker since most of the weight load is from above (vertical load).

I can see the frame buckling from too many holes in the sides vs too many holes in the bottom.
 
#21 ·
I suspect their concern is more of a modification in expected results in an accident, remember you have 3 holes on each side that become the crush zone for headon collisions. You tweak that and things could be disasterous (like you wearing the engine (exaggeration but you get the idea))
 
#23 ·
Most definitely but the placement of said holes was probably not pulled out of the air and I am sure to an (albeit small) extent modifying the existing structure would change the way the frame behaved in a collision and like I said above I am sure the rust that has been scaling off of the inside of what is now a minimum of a 10 year old frame probably has more of an impact than a couple small holes.
 
#26 ·
Drill 1/2" holes straight up through the hole in the lower control arm mounts front and rear. Spray the holes with chassis black paint. Flush your frame every time you wash the Jeep. Done. I also run fluid film inside and outside my frame during the winter. My frame looks as new on my '06 Rubi.
 
#28 ·
Pine_Cat said:
Since few chimed in, I'll float a theory. Maybe the FSM guidance is based on the assumption that the average user will never clean out the frame? For a vehicle that's only used normally, on the road, it's likely to be discarded because of mileage before the frame rusts through from the inside out. If you're not the average user, then, after you've driven through the mudholes, the only way to clean out the frame is to drill drain holes. After you've drilled the drain holes, then you're committed to annually flushing the frame, and should probably re-apply the Eastwood interior frame coating every few years. One may imagine that driving through the mudholes has a tendency to rinse off a water-based paint, so the Jeep's frame looks like it needs paint more than those of older vehicles that have not been offroad. IIRC other threads recommended plugging the drain holes that you've drilled so they're not open while driving? I hope my theory is right, because people have been drilling holes in their frames.
After drilling holes, I don't think you are any more committed to flushing the frame than anyone else is. There are so many other holes for dirt and debris to enter through I don't think a few more will make a marginal difference.

Same goes for plugging drain holes that are drilled. Why bother when there are other huge holes everywhere else?
 
#29 ·
After drilling holes, I don't think you are any more committed to flushing the frame than anyone else is
Yes, I should have checked my other trucks before floating my theory, sorry about that. All of my other trucks have drain holes on the frame's lower rail (even the Liberty's half frame). Bought my first special drill bit today, so I can flush my TJ's frame tomorrow. In some places, the sediment is piled up to the side holes.
 
#30 ·
I drilled mine and having personally had the frame on my last TJ rot out at the rear LCAs (from trapped muck I assume) I made this a priority mod on my current TJ, rinsed like crazy, and then did Eastwoods Internal.

BTW it was a pain to do. I used some titanium Dewalt bits and a 18V cordless, and it was slow going and some bits got broken.
 
#31 ·
I drilled mine and having personally had the frame on my last TJ rot out at the rear LCAs (from trapped muck I assume) I made this a priority mod on my current TJ, rinsed like crazy, and then did Eastwoods Internal.

BTW it was a pain to do. I used some titanium Dewalt bits and a 18V cordless, and it was slow going and some bits got broken.
When I'm drilling metal, I start small and then work up. I find it saves the bits, and I think goes about as fast, even with changeing bits 3-4 times to get to large size hole.
 
#33 ·
Pine_Cat said:
Uh oh, I didn't want to hear it's hard, since I'm new to doing my own work. Baptism by fire. Is the frame's metal too hard to use a step bit? Here's the one I bought: http://www.harborfreight.com/1-4-quarter-inch-3-4-quarter-inch-high-speed-steel-step-drill-44460.html
Those step bits work great, I've used them a ton. Don't spin too fast though or it will burn out. When drilling metal keeping the bit cool is the most important factor imo. A nice medium speed on the drill with some lubricant works wonders.
 
#34 ·
One other thing is worth mentioning, I wear glasses so I don't usually take any other protection for my eyes.

But since to drill frame holes requires you to be on your back laying under your work, be sure to wear proper eye protection, safety glasses/goggles.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top