Is the factory TJ frame electrically grounded to the body?

Zorba said:
Makes me wonder why I didn't originally have a good ground between the two.
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Because "dots" on body mount bushings are apparently a piss poor electrical solution.
And wire costs money, obviously the factory install works "good enough " for most cases.
But I agree with the wired bonding approach if you need it.
 
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ColoJeep said:
Because "dots" on body mount bushings are apparently a piss poor electrical solution.
And wire costs money, obviously the factory install works "good enough " for most cases.
But I agree with the wired bonding approach if you need it.
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It was certainly cheap and easy.
 
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Somehow the frame has a path to ground. It checks out with a multimeter and low amperage loads. However, it does not work for anything passing real current, Like zorbas winch. This makes perfect sense because there is not a direct connection from the battery negative to the frame. However, there is a connection and we can’t figure it out…
 
Are there any electrical components on a stock TJ grounded to the frame? My guess is no.
 
@mrblaine This is definitely far right field but the steering column in connected to the tub. I have never taken a TJ column apart but i assume it uses larger ball bearings,. The upper and lower steering shafts connect the steering column to the gearbox which is bolted to the frame. There is definitely a potential for a ground path here.

My other thought is brake lines.
 
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No there is not.

Aside from the things that you really don't want to use as an electrical ground like the brake lines Lou mentioned.

My custom LJ has zero conductivity between the axles, frame and the body (even accidentally tried welding). But the (relatively stock) TJ does when testing via multimeter.
 
Lou said:
Somehow the frame has a path to ground. It checks out with a multimeter and low amperage loads. However, it does not work for anything passing real current, Like Zorba's winch. This makes perfect sense because there is not a direct connection from the battery negative to the frame. However, there is a connection and we can’t figure it out…
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Its harder to completely isolate something like this than to purposely connect it! Looking like Jeep really did neither, which isn't optimal.
 
In my opinion Chrysler did not intend to have the frame grounded. If they did there would be a ground wire from the engine block or the firewall to the frame.
 
Reading through some old threads; I found one that mentioned a ground from the dipstick bolt area to the frame behind the passenger shock tower, and another mentioned one under the steering column to the frame.
No verification of either.
 
Lou said:
My other thought is brake lines.
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My opinion is the frame is not grounded in any electrical sense other than the brake likes like you suggested. I think the guy in this thread had a bad battery ground cable and installed a winch grounded to the frame essentially using his brake lines as ground cables. I suspected the steering gear too but I think all the bushings are isolated.
 
Lou said:
@mrblaine This is definitely far right field but the steering column in connected to the tub. I have never taken a TJ column apart but i assume it uses larger ball bearings,. The upper and lower steering shafts connect the steering column to the gearbox which is bolted to the frame. There is definitely a potential for a ground path here.

My other thought is brake lines.
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Well, I have the dash out of my 97 and I seem to recall a plastic isolator but I will check that. The shaft through the firewall is isolated as is the carrier bearing and lower steering shaft.

The brake lines are providing a connection in stock form. The frame end of the brake flex hose is steel, mounts to the frame with a bolt and the hard lines go from the combo block to the frame. The combo block is grounded to the firewall via the booster. Also explains why I know of several who have cooked the brake lines to red hot wiring up a winch.

Here is why the body mounts aren't providing a ground.
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toximus said:
My custom LJ has zero conductivity between the axles, frame and the body (even accidentally tried welding). But the (relatively stock) TJ does when testing via multimeter.
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I'm guessing that if you pulled the front brake lines loose at the frame, most of that would go away.
 
mrblaine said:
And I'm not referring to the early model ground strap that clips on the frame for killing static spark at the filler neck.

Or the little small gauge ground from the motor to the frame at the right side motor mount.

I'm talking about a real ground like you would use for actual electrical stuff of decent amp draw.
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My 98 I have only ever found the two you have mentioned. Ideally with no electrical items on the frame something for static is probably all that is needed.
 
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