wire connecting frame to body (ground wire???) 2002 XLT 4.6L 4WD

[LMHmedchem]

Hello,

In the middle of the frame on the drivers side there is a wire connecting the frame to the underside of the body. It is connected to the frame right under the middle body mount bushing and is less than 6" long. It connects to the body just above the bushing. The wire is relatively large and rather flat.

What is the purpose of this wire? I can only imagine that it is some kind of ground but there are no electronics in the area to ground other than possibly the rear door window motor. I cannot tell how this wire is connected. It is a standard loop connector on both ends but if there was a bolt, the head has long since rusted away. What is there looks like a post but I can't exactly tell what is holding the loop connector in place.

The wire is roached and stiff with cracked insulation. It should be replaced I'm sure but I don't know how to get it off or how to reattach a new one.

Suggestions would be appreciated,

LMHmedchem

 

[BKennedy]

It's probably a ground strap. It grounds frame and body so the electrical system doesn't know they are separate. It helps when smaller ground wires fail, or there is a short.

You could get a new ground strap and install it next to that one.

 

[LMHmedchem]

You could get a new ground strap and install it next to that one.

Do you have any idea what gauge it is? There seem to be quite a few options.

LMHmedchem

 

[Mbrooks420]

I’d use a 4 or 6 awg. I’d probably just get a copper jumper.

 

[BKennedy]

Do you have any idea what gauge it is? There seem to be quite a few options.

LMHmedchem

No idea, sorry

 

[Stynx]

just get a hunk of heavy copper wire and screw it in.

 

[Pete Deering]

Hello,

In the middle of the frame on the drivers side there is a wire connecting the frame to the underside of the body. It is connected to the frame right under the middle body mount bushing and is less than 6" long. It connects to the body just above the bushing. The wire is relatively large and rather flat.

What is the purpose of this wire? I can only imagine that it is some kind of ground but there are no electronics in the area to ground other than possibly the rear door window motor. I cannot tell how this wire is connected. It is a standard loop connector on both ends but if there was a bolt, the head has long since rusted away. What is there looks like a post but I can't exactly tell what is holding the loop connector in place.

The wire is roached and stiff with cracked insulation. It should be replaced I'm sure but I don't know how to get it off or how to reattach a new one.

Suggestions would be appreciated,

LMHmedchem

1. The purpose of ground wire is a connection too the PCM ( or make a path too). There's are a few moduless, dash cluster, tail lights etc, that uses the body or chassis as a ground path. The PCM has two ground pins (connection). Chassis ground and case ground.
2. The braided ground strap has greater resistant for it small surface area versus a round conductor. OEM strap are not cheap in price. I repair my straps but it did not last.
3 I than used 4 #10 building wire ( because that what I had available) with ring terminal and bolt and star washer and made ground studs to connect too. After installation I covered the connections with grease. Too keep the road salt off of them. Manufacturers typical require a #6 copper conductor as a minimum conductor.
4. I just notice that rockauto, is now selling ground strap around $8 each. At One time I trying to gather Ground strap at the JY. Very few vehicles had them.
5. There are about 8 ground straps thru out the vehicle
A. One under each front doors. By body mounts
B. The on the fire wall.
C. One to two on each front fender.
D. One to two on the radiator support.

 

[Pete Deering]

1. The purpose of ground wire is a connection too the PCM ( or make a path too). There's are a few moduless, dash cluster, tail lights etc, that uses the body or chassis as a ground path. The PCM has two ground pins (connection). Chassis ground and case ground.
2. The braided ground strap has greater resistant for it small surface area versus a round conductor. OEM strap are not cheap in price. I repair my straps but it did not last.
3 I than used 4 #10 building wire ( because that what I had available) with ring terminal and bolt and star washer and made ground studs to connect too. After installation I covered the connections with grease. Too keep the road salt off of them. Manufacturers typical require a #6 copper conductor as a minimum conductor.
4. I just notice that rockauto, is now selling ground strap around $8 each. At One time I trying to gather Ground strap at the JY. Very few vehicles had them.
5. There are about 8 ground straps thru out the vehicle
A. One under each front doors. By body mounts
B. The on the fire wall.
C. One to two on each front fender.
D. One to two on the radiator support.

Here's a chart

 

[LMHmedchem]

I should have everything I need here to make one up, though I am sure that the rest of them will need to be replaced as well. I am sure I have both 4 and 6 AWG and crimp on loop connectors.

I would probably solder on the loops and add some heat shrink tubing for insulation. I have plenty of all of that.

Is there any reason to buy one of the braided wires instead of making up my own?

It's not at all clear what's holding on the existing straps. There is definitely a stud, but It doesn't look like there is a nut. If there was a nut, it's long gone. It may have been secured with a blob of solder or epoxy or something like that. I will probably just drill and tap some holes for M6 stainless steel hex bolts. I have a box of those and the tap and bit set. 304 stainless doesn't conduct quite as well as plain steel but the main conducting point will be contact against the frame and body and not through the stud. I will grind the contact point down to something nice and shiny before I install.

LMHmedchem

 

[Mbrooks420]

That’ll work fine.

 

[BKennedy]

What Brooks said. I think the reasoning for so many ground straps is Ford expected them to fail over time. If this is a daily driver, I would replace them over time, starting with the most corroded. If it was a trail rig where I was 50 miles from a paved road on a regular basis, I would replace them all at once.

Interesting that Ford used so many straps on this model, and my 1994 has a strap grounding the engine block to the firewall, and the main battery grounds to the engine and frame. I added an auxiliary battery that grounds to both body and frame. That's it. More electronics, more grounds.

 

[Pete Deering]

I should have everything I need here to make one up, though I am sure that the rest of them will need to be replaced as well. I am sure I have both 4 and 6 AWG and crimp on loop connectors.

I would probably solder on the loops and add some heat shrink tubing for insulation. I have plenty of all of that.

Is there any reason to buy one of the braided wires instead of making up my own?

It's not at all clear what's holding on the existing straps. There is definitely a stud, but It doesn't look like there is a nut. If there was a nut, it's long gone. It may have been secured with a blob of solder or epoxy or something like that. I will probably just drill and tap some holes for M6 stainless steel hex bolts. I have a box of those and the tap and bit set. 304 stainless doesn't conduct quite as well as plain steel but the main conducting point will be contact against the frame and body and not through the stud. I will grind the contact point down to something nice and shiny before I install.

LMHmedchem

1. Don't solder, just crimp connector. The solder will not last.
That's what is used by the factory for all there connection.
2. The clip are pressure connector. They lock on to the frame.
3. I added a stud. Use your SS bolts, with star washer and nuts, to secure the bolt as a stud. then add the ring connector and secure with a nut.
Don't tap the connector is not that conductive.
4. I think you have to reuse the factory ground clips on the body and or for the frame.
5. Coat the finished connection with grease.
Just for information there are 18 ground connection on my explorer from the factory.

 

[Mbrooks420]

No reason you can’t simply drill a new hole, clean around it, and tap the frame. This will provide a more than suitable ground. Using the proper solder/paste would be fine if you want to go that route.