How long will rusty TJ frame last?

Roger. So, other than cruising down the street and all of a sudden having 1/2 of the jeep crash down to the side, I assume I should just be keeping an eye out for holes, and keep poking around periodically? All the cleaning and spray work that gets done, does that have to be frame off?
Also, I can probably guess the answer, but is it really, really stupid to try to off road this a little bit, or is it just a kind of thing that if it’s gonna break it’s going to break?
 
The actual cost for the two caps is around $900 I think, from Auto Rust Technicians. (https://www.autorust.com/product-category/jeep/jeep-tj/) You'll want the full-length caps almost certainly as you likely have rot near the rear control arms. You can also get caps from Pocono Metal Craft, and they're a bit cheaper, but I can't speak if the quality is comparable. If installed right (i.e. cutting out ALL of the existing rust), they will outlive the rest of the Jeep. The reason the frame rotted out is because the factory did not include drain holes, so water and salt pooled inside over years and years. The caps do come with a drain hole, so you should be set.

Thanks for that recommendation. Yes, I wonder why after about five years they didn’t start drilling holes. Maybe so they could sell more jeeps.
 
If you are not able to remove the skid plate, the Jeep is not safe to drive. Either you decide to not remove the skid plate and immediately patch the frame or you remove the skid plate to check for rot. You can't drive a rusty TJ frame around the road blind to how rusty it is. Better to know your frame is falling apart than to have it happen on the highway.

I guarantee you that frame is rotting under that skid plate. If he removes it to find rot, he will find rot, and then he likely will have to cap it immediately because there is no getting that plate back on. I do agree with you in principle—no one should be driving an unsafe vehicle. If it were my Jeep, I'd do the right thing and cap it right now if the rest of the tub is OK.

However, if he is not dailying the Jeep and just wants to bounce around on the trails before figuring out whether to cap the vehicle, it's not a huge deal to wait a little while as long as there are no cracks in the frame near the rear control arms—that's where the real danger is in terms of safety.
 
If you don’t mind my asking, were the caps about two grand like was mentioned above? I would be willing to drop two grand if I were fairly certain those would hold for several years. It would be cool to work on this jeep with my son, so like I said, almost anything that isn’t the frame I don’t mind messing with and replacing myself. I just need the frame to be safe. I have an arc welder, but I guess since I haven’t used it in two years, I’m not going to be using it.

I wouldn’t recommend doing it at home. Each patch was $550 in the center, he CNC cuts his own and welds in. Each rear control arm was $400 with the SafeTCap provided. Axle was $500 for both lower control arms and $450 for the spring perch.

Imagine if I just bought a cleaner Jeep? lol
 
I guarantee you that frame is rotting under that skid plate. If he removes it to find rot, he will find rot, and then he likely will have to cap it immediately because there is no getting that plate back on. I do agree with you in principle—no one should be driving an unsafe vehicle. If it were my Jeep, I'd do the right thing and cap it right now if the rest of the tub is OK.

However, if he is not dailying the Jeep and just wants to bounce around on the trails before figuring out whether to cap the vehicle, it's not a huge deal to wait a little while as long as there are no cracks in the frame near the rear control arms—that's where the real danger is in terms of safety.

That is a good point. If it will see no road time, don't bother with the skid plate until it fails. If you are driving on the road, take it off and see whats happening underneath there. You will likely have to patch it for it to be safe.
 
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These are the SafeTcaps in the rear

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I'm going to play devil's advocate here and say not to remove the skid plate. I think we should assume much of the frame is rotted away underneath having seen those pictures. Removing the bolts might break free the nutserts. At this point I think you want to milk as much as you can out of this frame before determining whether to do a safe t cap job.
I agree with this. The frame is guaranteed to be rusted underneath and the nutserts are going to break free if you try to remove the skid. This happened to my Jeep that was honestly in better condition than this. But I was in the process of lowering the skid and had to get caps to put it back on. It probably would have lasted a few more years if I never touched it. The bolts are not going to break free all at once but definitely check them periodically.
 
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Alright, thanks everyone for the perspectives. I probably will not pull the skid plates. My impression based on what I have read over the last few weeks was that a frame wasn’t getting to an unsafe point until it has started to develop holes, or spots soft enough to break holes through. I’m not a professional metallurgist, but I understand rust. In part I was just curious to see how this pretty rusty TJ compares to others people have seen. Again, I live in Minnesota so this is not even close to the rustiest frame I’ve seen. I’m scheduled to have my mechanic service it and do a whole vehicle inspection this weekend, so I’ll see what he says about it. Thanks again for the feedback.
 
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I live in Minnesota so this is not even close to the rustiest frame I’ve seen. I’m scheduled to have my mechanic service it and do a whole vehicle inspection this weekend, so I’ll see what he says about it.
Best choice for sure. I'm from Alberta, we have the same issues. I'd say keep it on pavement or good smooth gravel til you know the frame will take a bit of flexing. Rust is a bitch but until a bolt falls out or you can punch holes in it drive with care. Me, I'd want to replace the frame..... or buy a rust free beater and use those low milage parts on it. I'll guess you got it for a rock bottom price.

Enjoy the TJ experience, they are a blast even as grocery getters.
 
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I'd drive it until there are holes / cracks or other issues like the skid coming loose. Then I'd buy a clean frame from the south off car-part and have it shipped. Swapping in a clean southern frame is about the same as caps if you can do it yourself. Caps are ok, but its still a "repaired" rusty frame. Either way, enjoy it, that's why you bought it in the first place.
 
Best choice for sure. I'm from Alberta, we have the same issues. I'd say keep it on pavement or good smooth gravel til you know the frame will take a bit of flexing. Rust is a bitch but until a bolt falls out or you can punch holes in it drive with care. Me, I'd want to replace the frame..... or buy a rust free beater and use those low milage parts on it. I'll guess you got it for a rock bottom price.

Enjoy the TJ experience, they are a blast even as grocery getters.
One thing I’ve always wondered, how would my Jeep fair if I were to lift it and throw on bigger tires.
She currently does 80.. sometimes 85 for a quick second.. down the NJ highways without an issue. Wonder how that compares to slowly crawling over rocks lol
 
If you do try to remove the skid I would squirt a ton of pb blaster I there before drilling a hole and let it soak.
 
Some dangerous advice in this thread. If you are going to be driving this on public roadways at speed, do not ignore the frame. If you are unable to drop the transfer case skid without problems, the Jeep is too rotted to drive on the road.

No recommendation should be to stay on road with the Jeep because going off-road may break the frame. If off-roading breaks the frame, it is too unsafe to drive on the road.

I don’t think this frame will snap in half if you drive it. But why not just figure out the extent of the damage before you figure it out at 65 mph? Just fix it and get it done with before you encounter a larger problem.
 
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Some dangerous advice in this thread. If you are going to be driving this on public roadways at speed, do not ignore the frame. If you are unable to drop the transfer case skid without problems, the Jeep is too rotted to drive on the road.

No recommendation should be to stay on road with the Jeep because going off-road may break the frame. If off-roading breaks the frame, it is too unsafe to drive on the road.

I don’t think this frame will snap in half if you drive it. But why not just figure out the extent of the damage before you find them at 65 mph? Just fix it and get it done with before you encounter a larger problem.

X100 to this
 
Some dangerous advice in this thread. If you are going to be driving this on public roadways at speed, do not ignore the frame. If you are unable to drop the transfer case skid without problems, the Jeep is too rotted to drive on the road.

No recommendation should be to stay on road with the Jeep because going off-road may break the frame. If off-roading breaks the frame, it is too unsafe to drive on the road.

I don’t think this frame will snap in half if you drive it. But why not just figure out the extent of the damage before you figure it out at 65 mph? Just fix it and get it done with before you encounter a larger problem.
All of my frame sections had noticeable holes for a couple months before they were bandaided or patched. Mostly due to funds. I didn’t have an issue with mine falling apart, but not every frame is going to be the same.

I still wouldn’t recommend it. My commute was never far from home. But you bet I was worrying every drive about it falling apart. Wouldn’t be a bad idea to get it cut out and replaced before it gets too bad. I’m happy I have had mine done and don’t question the integrity of it anymore.

But like I said, my Jeep is stock aside from 32s. No rear spare no back seat etc. So I can’t comment on the integrity of a frame patched one that’s lifted with all the heavy goodies attached to it. Haven’t read anything online about frame patches falling apart though
 
All of my frame sections had noticeable holes for a couple months before they were bandaided or patched. Mostly due to funds. I didn’t have an issue with mine falling apart, but not every frame is going to be the same.

I still wouldn’t recommend it. My commute was never far from home. But you bet I was worrying every drive about it falling apart. Wouldn’t be a bad idea to get it cut out and replaced before it gets too bad. I’m happy I have had mine done and don’t question the integrity of it anymore.

But like I said, my Jeep is stock aside from 32s. No rear spare no back seat etc. So I can’t comment on the integrity of a frame patched one that’s lifted with all the heavy goodies attached to it. Haven’t read anything online about frame patches falling apart though

It’s probably not going to fall apart, but why let it get worse? I wouldn’t want to drive around without knowing 100% my frame was in tact.
 
Probably not qualitatively rock bottom, but I got it for low blue book. There is some body rust here and there that will be pretty easy to fix. There are one or two bondo spots. But aside from frame it’s in overall excellent shape and low miles for that I6. I figure if I drop a decent amount on caps at one point or another, keep it well-maintained, which is how I roll, could at least break even after having fun for a couple years. Then see if I want to spend 15k on a little bit newer one with clean frame, which is at least how much they go for here, even with high miles.
 
Some dangerous advice in this thread. If you are going to be driving this on public roadways at speed, do not ignore the frame. If you are unable to drop the transfer case skid without problems, the Jeep is too rotted to drive on the road.

No recommendation should be to stay on road with the Jeep because going off-road may break the frame. If off-roading breaks the frame, it is too unsafe to drive on the road.

I don’t think this frame will snap in half if you drive it. But why not just figure out the extent of the damage before you figure it out at 65 mph? Just fix it and get it done with before you encounter a larger problem.

Totally agree. I trust everyone’s eyeballs and experience here, but I’ll feel most comfortable after my mechanic puts hands on it and gives me an assessment. If he says it’s bad, good news is there’s a SafeTCap installer shop an hour from me. I would love to do a frame swap, but although I’m pretty mechanically inclines, I don’t know if I’m up for that task. I have a little cushion to spend on repairs. Clean frame would be ideal, but fixed frame that will last a few years is more in my budget. I do t want to give the impression that I’m going to thrash on this thing and/or be spending a bunch of time on the highway. Just slow, easy miles close to home for now.