4x4labs bumper installation: crossmember cutting (1 Viewer)

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Anyone know how much to chop off to install the bumper? Also do i use my existing hardware to install it?
 
Yes, save your hardware, you will need the bolts to mount the new bumper. Here are a couple of pics showing how much I cut off my frame rails:
DSCN3598.JPG
DSCN3724.JPG
 
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Cant wait to get one for my LX.

Rwhat: Any problems fitting the side plate upper tubes with the LX moldings?
 
Are you using a sawzall to make those cuts? Or a cut off wheel on a grinder?
 
At one time Luke maintained a copy of the bumper installation instructions on their web site. I have a copy but on another computer I currently do not have access to. Give them a call, they should email you a copy.
 
Cant wait to get one for my LX.

Rwhat: Any problems fitting the side plate upper tubes with the LX moldings?

Dont know yet, this one was previously fitted to a LC. I might have to grind the welds off and reweld it out farther to clear the moulding. Luckly Labs only did like 5 stitch welds on the inside of the bar.

Thanks for everyones help and pics.
 
Anyone know how much to chop off to install the bumper? Also do i use my existing hardware to install it?

There are three big threaded holes in each side of the bottom of the frame, the ones used to hold the hitch on. The two forward ones are used to hold the Luke bumper on, so it needs to be cut between the two rear most holes. I attempt to cut as close to the second hole as possible without hitting the nut, so about 1/2" back from the edge of the hole.
 
Here is the diagram from the install doc, if want the whole doc let me know.

frame cut.jpg
frame cut.jpg
 
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I don't see the point of the extra angle cut, I just cut them at the nut.

Either way will work, the only reason I can figure is that it would give the top of the bumper a little bit more of a lip to sit on. :meh: This may help in aligning bumper during the install. The pic was straight from Luke's doc.
 
I'm about to install my bumper this weekend. Is there any other debate on doing the angle cut like this or the straight cut just behind the second nut?

Straight cut , additional angle cut is more work and pointless
 
Cut it straight on mine.
 
Are you using a sawzall to make those cuts? Or a cut off wheel on a grinder?
I used a sawzall on mine. It cut like buttah. I did the little angle thingie too, but it probably wasn't necessary...
 
I used a sawzall on mine. It cut like buttah. I did the little angle thingie too, but it probably wasn't necessary...
Same here. Have a couple extra good blades on hand. And, yes, those measurements you listed are correct @rockstate45 .
 
And you'll most likely need to chop off some of your exhaust. See pic above where the LX cut his off.
 
Thanks for the responses, guys! Looks like we're okay without doing the angle cut at the bottom but I wonder if that extra little bit makes a difference for vertical forces? (Again, I'm speaking from pictures and not having chopped my frame yet)

Per the pics, it looks like the resonator will be gone with this install.

Big thanks to @FZJ80 in KC for helping getting this shipping put together - probably wouldn't have happened this year without his help.
 
I did the straight cut just aft of the nut with a sawzall. IIRC, I took off about 4". I measured back from the centerline of the mounting hole in the bumper to the inside weld bead (because that it what's going to hit first) and then marked my frame rail to clear that dimension. I've still got the frame rail/cross member laying in the garage. White tape with the vertical line on it was where I cut...

Yep, resonator will be gone.

Rbumper3.JPG


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