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DIY: $15 grounding kit
Posted: Sat Oct 16, 2004 5:53 pm
by 90LegAWD
here's my $15 grounding kit. anyone with 10+ year old OEM grounds that are corroding and starting to turn green needs to do this. 90% of all 10+ yr old car electrical problems are because of a bad ground signal.
here's what you need:
one 12" 4gauge top post style battery ground $5
one 32" 4gauge battery cable $5
one 16" 4gauge battery cable (optional) $5
the install:
12" top post goes from the battery to the OEM radiator support grounding point
32" cable goes from the battery terminal to the tranny ground
16" cable goes from the tranny ground to the firewall
here's the 32" cable connection to the battery terminal
if you really feel ambitious, you could take this a step further and connect a wire from the tranny ground to the alternator mounting bracket, but it's not essential.
the engine starts instantly now, the door locks and windows work twice as fast as they use to, and the engine seems to run a lot smoother.
Posted: Sun Oct 17, 2004 8:54 am
by tris91ricer
dude, you straight ROCK. i've been looking to create something like this for quite some time now.. i hate spending good scrill for something we could all make at HD... nice work, i commend you.
oh well, someone had to beat me to it.. never have time..
thanks!
Posted: Sun Oct 17, 2004 3:42 pm
by sullione
I hate to sound stupid but should the older grounds be left in place? I really think my car will benefit from this because all of my battery wires are starting to corrode. I just replaced the fitting on the little one that runs from the chassis (just above the round tranny filter) and when I cut it, it was corroded. It looks as if its corroded all the way so I need to replace it.
Posted: Sun Oct 17, 2004 4:27 pm
by 90LegAWD
i removed my OEM ground wires. they were near worthless anyway.
both my 94 and my wife's 90 L wagons were corroded
Posted: Sun Oct 17, 2004 8:24 pm
by sullione
I think I will remove my old one too. How many are there? Did you just replace the originals with this setup or was this a reroute?
Posted: Sun Oct 17, 2004 9:14 pm
by Legacy777
I did something similar to this a while ago. Except I added additional ground wiring, and left the old ones there.
I just ran an extra ground strap to the chassis and starter spots.
I don't know if I'd consider this the same as the multi-point grounding kits, but I'm sure it'd probably help especially on the older cars.
Posted: Sun Oct 17, 2004 11:05 pm
by vrg3
This procedure is basically just replacing the factory negative battery terminal wire, with the addition of a strap to the firewall.
The stock wires were marginal even when they were brand new, so it's easy to see how this improves starting and charging and stuff.
Posted: Tue Oct 19, 2004 1:42 am
by sullione
90LegAWD, where did you buy your cables? This stuff is alot more expensive around here from what I've seen. Where can I pick these same cables up?
Posted: Tue Oct 19, 2004 3:32 am
by syphon
Where exactly is the tranny ground?
Posted: Tue Oct 19, 2004 6:27 pm
by tris91ricer
I think its somewhere near the starter, correct? i would assume that they would share a ground?
Posted: Tue Oct 19, 2004 7:37 pm
by 90LegAWD
tranny ground is in the 3rd pic to the left side
i got mine at pepboys. i know that most chain stores have these for sale
Posted: Tue Oct 19, 2004 10:27 pm
by syphon
Hehe, don't confuse the tranny ground with the Power wire for the starter. The power wire for the starter is the one with the little rubber cover over it

Posted: Tue Oct 19, 2004 11:36 pm
by Legacy777
yup....tranny ground is a little wire that usually breaks. It was gone on the tranny I put in, I rewired a new one and hooked it up.
Posted: Wed Oct 20, 2004 1:07 am
by mikec
Legacy777 wrote:yup....tranny ground is a little wire that usually breaks. It was gone on the tranny I put in, I rewired a new one and hooked it up.
Mine had the ring connector on the tranny, but nothing else... No wire, just a bit of corroded wire on the connector. I also put a new one on.
I may look into redoing my stock starter ground in a similar fashion...
Posted: Wed Oct 20, 2004 1:35 am
by syphon
I just did this exactly as the original poster described.
-4ga terminal, connecting the battery to the radiator support.
-4ga wire from the terminal to the tranny ground point.
-4ga wire from the tranny to the firewall.
-4ga wire from the firewall to the alternator mounting bracket.
Didn't notice a difference at all. My car still hesitates, my power windows are still very slow, etc. etc. Oh well, I probably have a few different problems.

Posted: Wed Oct 20, 2004 6:19 am
by BAC5.2
I grounded my battery in the trunk.
Posted: Wed Oct 20, 2004 3:26 pm
by Brat4by4
Didn't notice a difference at all. My car still hesitates, my power windows are still very slow, etc. etc. Oh well, I probably have a few different problems.
Did you make sure to clean all the contact points before installing all the new stuff? You need a stiff wire brush or ideally some sand paper. Also spray all the new connections down with WD40. It displaces moisture and is a rust inhibitor.
Posted: Sat Aug 20, 2005 12:43 am
by climbingjunky
Todays project was re grounding my 93 legacy and I must say I was quite suprised what $20 in wire and connectors can do. Before my windows would crawl now they are noticably quicker. The first time i tuned the key after installing the new grounds it started right up. now i just got to get her out and driving a little to see if there is any enhancment in the hesitation factor. I would recommend that everyone with an older model car think about doing this some afternoon. Here is an outline of how i connected grounds.
All wire is 10g power wire.
1. battery to right strut mount ground
2. battery to left sturt mount ground
3. battery to tranny ground to firewall
4. battery to ground on head to alternator ground
there are a lot of wires coming off of the negative terminal of my battery now, but if it makes my subby fire right up it is worth it!
Posted: Thu Aug 25, 2005 11:17 pm
by mnlegacy
i juyst got done doing this, used wire from battery to radiator support,wire from drivers strut to tranny to firewall, from left strut to intake manifold. revs much easier, no hesitation, locks work faster, as do windows, i used wire i had laying around, well i cut it off a pair of old jusmper cables, so its like 4-6 gauge, not sure if 4 gauge normal wire would work better or not, if you knwo please tell me, i am impressed witht he results already, so if it could be better i would be even happier,let me know thanks
Posted: Fri Aug 26, 2005 7:37 pm
by tris91ricer
This thread is used/referenced quite a bit, and integral to the grounding discussion. When will it get a sticky?
Posted: Sat Aug 05, 2006 7:59 pm
by wongstein
This is great information! How can I get the pictures?
Thanks fellas,
Anthony
re
Posted: Mon Aug 07, 2006 6:18 pm
by theflystyle
yeah looks like the links to the pics got messed up... can you re-host them???
Posted: Tue Aug 08, 2006 10:53 pm
by tris91ricer
Mods, please make this thread a sticky. I know its effects aren't exactly proven effective, but, its a good starting point, with pics, for anyone who wants to explore different grounding techniques.
Posted: Fri Aug 25, 2006 5:57 am
by wongstein
The only reason that I wanted pics was to know what all the terminations look like. Are they all just like the ones to the battery? I guess I could just inspect them all myself, but I'm still waiting for my Haynes manual to arrive.
Thanks,
Anthony
Posted: Wed Sep 06, 2006 4:27 am
by snowman
I don't mean this as showing off...I just decided to carry my HD electrical a step further, since I plan to take my car where it gets to 50 below during the winter.
About a month ago, I redid all my battery and ground cables and installed dual batteries. I used two NAPA orbital 750-CCA batteries. Each positive post connects directly to the starter with a 000-gauge fine-strand arctic-rated cable (including the insulation, the cable is about as big around as your thumb). Each negative post connects to the factory engine/tranny ground point with the same type of cable. I also redid the radiator-support cable and the alternator-to-battery cable with 2-gauge fine-strand arctic-rated cable.
Holy crap, this thing cranks fast now! I never had any problems with slow windows and such before, so I don't know if it made any difference there. The voltage drop is also much lower across most of the cables, so the charging voltage at the battery itself is higher.