Any advice before I drill frame drain holes?

Tim_with_the_tj

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Vancouver, WA
I’ve read a bunch of threads on the topic. Any last advice I should know before drilling drain holes in the frame? I plan to drill four holes total, one front and one rear drain hole per side.
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I’m also seeing lots of mud getting trapped in the front part of the torque boxes. Any advice for the best way to wash that out without having to blast it all the way out the rear of the tub? That first big drain hole is stamped upwards so it doesn’t drain mud well.

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I wish I knew before also. I had to replace my frame. Make sure you put holes in front of the rear bumper/crossmember also. I didn’t see it in your photos.thats where mine rotted out first.
 
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I’ve read a bunch of threads on the topic. Any last advice I should know before drilling drain holes in the frame? I plan to drill four holes total, one front and one rear drain hole per side.
View attachment 303340

View attachment 303341

I’m also seeing lots of mud getting trapped in the front part of the torque boxes. Any advice for the best way to wash that out without having to blast it all the way out the rear of the tub? That first big drain hole is stamped upwards so it doesn’t drain mud well.

View attachment 303342
0.5” should be sufficient. Paint the hole after.
 
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Remove the rear bumper and drill two holes (1 per side) like this (Note the crud!):
3b0.jpg


THEN - this out of focus picture sucks - but shows well enough to slot this hole down as shown. Otherwise, there's yet another rust vector...
3c1.jpg

The large hole is where the bumper bolts onto - no drain there. The slotting will enable water to run out below the level of the bottom of the inside of the frame as the rear crossmember wraps UNDER it.
 
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I wish I knew before also. I had to replace my frame. Make sure you put holes in front of the rear bumper/crossmember also. I didn’t see it in your photos.thats where mine rotted out first.
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It drains well here. Nothing is trapped behind that hole. No water or mud. I think this is a factory hole. Is this what you were saying?
 
My po drilled holes by the front lowers but not the rears. Am I okay or should I drill additional holes?
 
Yes, drill it. You want drain holes in the locations shown on the frame in post #1.
I know it’s not quite in the lowest but I drilled(4)1/2 inch holes through the holes that already in the lower control mounts since they are reinforced.then ran a harbor freight drain cleaner wit 4 links of chain and Eastwood frame coating,all good now
 
Lol. It must be inside that rear crossmember where I can’t see it then? Inside the frame rail rearward of that drain hole is clear of water and debris.
Mine wasn't - but its really hard to describe in words. The rear cross member wraps under the bottom of the frame. There is - at least on mine - a 1/8 inch-ish gap between the end of the frame and the inside surface of the cross member. This cannot drain unless a slot is cut. Overkill? Perhaps - but I'm paranoid about rust! YMMV and all that...
 
Mine wasn't - but its really hard to describe in words. The rear cross member wraps under the bottom of the frame. There is - at least on mine - a 1/8 inch-ish gap between the end of the frame and the inside surface of the cross member. This cannot drain unless a slot is cut. Overkill? Perhaps - but I'm paranoid about rust! YMMV and all that...
I will remove and take a look behind the rear bumper after drilling the four typical frame drain holes. There is one bolt that’s snapped off in my rear bumper from a previous owner. When I remove the bumper I’m gonna drill that broken bolt out and I’m not looking forward to it… so in my mind this is a whole ‘nother job besides drilling the frame drain holes. Lol
 
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