Cab-to-Engine Ground
Thread Starter
|
Senior User
Joined: Aug 2008
Posts: 187
Likes: 0
Cab-to-Engine Ground
How is the temperature sending unit grounded on these trucks?
When I got this truck, a ground wire was bolted from the firewall by the throttle linkage down to the transmission case (AOD). The firewall connection had a second wire that went to a connector that connected to a wire to the engine computer. There is another engine block-to-frame ground through the negative battery cable.
Does that sound right? Why is the transmission case grounded?
I just finished a Duraspark conversion on my 1984 F150 (302), and I noticed the older models had a single ground wire that connected from the firewall to the intake manifold. My truck doesn't have this ground at all. I am running an aluminum intake manifold, if that makes a difference.
When I got this truck, a ground wire was bolted from the firewall by the throttle linkage down to the transmission case (AOD). The firewall connection had a second wire that went to a connector that connected to a wire to the engine computer. There is another engine block-to-frame ground through the negative battery cable.
Does that sound right? Why is the transmission case grounded?
I just finished a Duraspark conversion on my 1984 F150 (302), and I noticed the older models had a single ground wire that connected from the firewall to the intake manifold. My truck doesn't have this ground at all. I am running an aluminum intake manifold, if that makes a difference.
Posting Guru
Joined: Aug 2009
Posts: 2,271
Likes: 2
From: Mexia, TX
The DSII box grounds through the black wire from the distributor, I think. If you've got the engine and transmission grounded separately then I would think that'd be enough. I'm running a C6 and I don't have it connected to ground, though I could see a grounded transmission case helping the starter out some (since it grounds through the engine and transmission).
I added an addition 4 gauge wire from battery negative to the front passenger side frame rail. Not necessary but some stuff grounds to the frame so I went ahead and did it.
I added an addition 4 gauge wire from battery negative to the front passenger side frame rail. Not necessary but some stuff grounds to the frame so I went ahead and did it.
Laughing Gas
Joined: Sep 2012
Posts: 1,100
Likes: 6
From: Georgia
I always prefer a ground directly to the engine block, so the starter has the best circuit it can.
Some of my vehicles I run a ground from the battery to the frame and from that bolt one to a starter bolt and a smaller gauge, #6 or so, from the battery to the body.
On my 460 I have a ground from the battery to the block at the front and from that bolt one going to the frame.
Some of my vehicles I run a ground from the battery to the frame and from that bolt one to a starter bolt and a smaller gauge, #6 or so, from the battery to the body.
On my 460 I have a ground from the battery to the block at the front and from that bolt one going to the frame.
Moderator
Joined: Jan 2001
Posts: 56,997
Likes: 2,743
From: Virginia
It doesn't matter, the engine and the tranny are bolted together as one. The intake and the engine are bolted together as one also.
The reason you have to run grounds to the engine/tranny is because the main heavy ground wire from the battery bolts to the engine block somewhere(usually on the front pass corner of the engine). But the engine/tranny are mounted in rubber motor mounts, as well as the rearend which is mounted to the springs which are mounted in rubber bushings.
So you need these little ground straps to ground the body. The factory also had a spot where they grounded the frame, but if the ground cable gets replaced you may have lost this part. But even when the frame is grounded, the body still won't be grounded. It's mounted in rubber body mounts, and the bolts do not touch the frame.
The reason you have to run grounds to the engine/tranny is because the main heavy ground wire from the battery bolts to the engine block somewhere(usually on the front pass corner of the engine). But the engine/tranny are mounted in rubber motor mounts, as well as the rearend which is mounted to the springs which are mounted in rubber bushings.
So you need these little ground straps to ground the body. The factory also had a spot where they grounded the frame, but if the ground cable gets replaced you may have lost this part. But even when the frame is grounded, the body still won't be grounded. It's mounted in rubber body mounts, and the bolts do not touch the frame.
Moderator
Joined: Jan 2001
Posts: 56,997
Likes: 2,743
From: Virginia
Trending Topics
Laughing Gas
Joined: Sep 2012
Posts: 1,100
Likes: 6
From: Georgia
I use dielectric grease on all electrical connections (with a few exceptions) because it's not electrically conductive. For me it's easier to have just one grease for all electrical. But yeah, on a ground connection pretty much any grease is fine.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Thread
Thread Starter
Forum
Replies
Last Post
JayBourbon
1987 - 1996 F150 & Larger F-Series Trucks
1
Dec 29, 2017 10:23 AM
Brnfree
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
11
Apr 19, 2013 11:10 AM
wickedmax13
1987 - 1996 F150 & Larger F-Series Trucks
4
Aug 14, 2010 08:53 PM