Leaking coolant (freeze plug?), okay to drive?

I've been having a small amount of coolant leaking from the rearmost part of my 4.0L. I suspect it may be the freeze plug(s) on the back of the engine since it's dripping onto the same spot as my rear main leak, haha.

It's not leaking much, but when the weather warms up it seems to leak even if I haven't driven the Jeep in a few days or more. It's been leaking like this for a few months and I generally drive the Jeep a couple times a week, maybe about 40-50 miles in total each week. It runs fine, and I haven't had to top off the coolant much at all.

I'm just wondering how much longer I can safely drive the Jeep if it is indeed a rear freeze plug leaking, assuming I keep the coolant topped off. I have a camping trip coming up at the end of the month which is about a 1.5 hr highway drive each way. I won't have time to fix the issue before then, so I'm wondering if I should be okay to drive the Jeep or if that would be risky.

No one can answer this question unless they have x-ray vision.

My 2001 XJ developed the same leak, so I pulled the engine.
I found one of the rear casting plugs almost totally gone. It was backed up by a blob of solidified casting sand, left over from when the engine was cast. The sand may have helped it corrode but it also reinforced the plug.

It was just a matter of time before it would have blown out, most likely on a hot day, on a long upgrade.

When you burn up your engine you will have answered your answer to your question on how long you can you safely drive it. Be sure to get back to us, so the rest of us will know the answer.:huh:

The answer to the question is fix it before the vacation, or the engine, is ruined.

Freeze plug problems really suck; I had one corrode under the manifolds and replaced all the side galley plugs. Sadly I used a junk non-brass set and one popped out on me six months later on the way out to the desert. Thankfully it did it on the highway within quick AAA range of my house and not two hours later, 20 miles off pavement and a five mile hike from cell service.

I tore it all apart again and reinstalled them with a nice brass set. Reinforced each one with JBWeld because paranoia. I think the damn thing is still weeping a tiny bit, but as long as it stays in. ..

I didn't notice mine was bad when I bought it at 186,000. Who knows how long it had been leaking, or how long it would have gone. For what it's worth, I stressed the old bad one pretty hard on hot grades until I discovered it. If you want to risk it, depends on where you're going on your vacation, how remote, etc.

I had that problem to solve when I got my Jeep. I knew the owner so it wasn't a surprise and she drove it like that for awhile too. I would say to just judge the amount that is leaking out, how much are you topping off. I drove mine for awhile that way til I got bigger problems fixed.

Tip: put a long screw in middle. Long screw is piece of mind if it falls inside block it won't fall far. Use some aviation sealer like in the link below. Old chevy guy showed me this stuff years ago. Put it on the rim of freeze plug, brass, as was said before. Let it cure. Your plugs won't leak or pop out. This stuff is the real deal, yeh it will be a bitch if you ever want to take them out again.

http://www.amazon.com/Permatex-80017-Aviation-Form-A-Gasket-Sealant/dp/B000HBM42Y

I see it at most parts stores.

Royal Nonesuch said:

Freeze plug problems really suck; I had one corrode under the manifolds and replaced all the side galley plugs. Sadly I used a junk non-brass set and one popped out on me six months later on the way out to the desert. Thankfully it did it on the highway within quick AAA range of my house and not two hours later, 20 miles off pavement and a five mile hike from cell service.

Click to expand...

I had one pop out on me like that going up the pass over Hood in my chevy. Dad brought me a temporary rubber one with the bolt in it that tightens to fit any hole. Aviation sealer applied to next one, holds em good.