Glow plug relay
Postmaster
Joined: Apr 2001
Posts: 3,628
Likes: 0
From: Baileyton, TN
I should know, but can't remember. If nobody has posted the reply by tomorrow morning, I will look at the '02 and let you know. I am not prepared to go look tonight, because it is raining hard, and I shrink in the wet... 
Theo
Theo
Mountain Pass
Joined: Sep 2002
Posts: 148
Likes: 6
This is somewhat of a guess on exact location but it is behind the fuel filter. Look for a round component about 1 1/2 inches in diameter with heavy gauge, say #10 wires connected to it. All of mine have had a plastic cover on them which slips over top the two bolts that the wires connect to.
If you suspect a problem with it, use an ohmmeter and :
remove the wires and measure the resistance, with key off. If you get any resistance at all, the contacts are slightly shorted out. This is not uncommon and will lead to premature glow plug failure since you are apply some voltage to the glow plugs all the time.
Then have your digital volt meter ready while someone turns the key on, in voltage mode, dc, put your two probes, one on each of the bolts where the wires are connected. If you get any voltage reading, there is a voltage drop across the contacts. The higher the voltage, the worse the drop. The drop is caused by the contacts burning and the conductive surface is not even.
If you find either of these reading above to be true, replace the relay.
If you suspect a problem with it, use an ohmmeter and :
remove the wires and measure the resistance, with key off. If you get any resistance at all, the contacts are slightly shorted out. This is not uncommon and will lead to premature glow plug failure since you are apply some voltage to the glow plugs all the time.
Then have your digital volt meter ready while someone turns the key on, in voltage mode, dc, put your two probes, one on each of the bolts where the wires are connected. If you get any voltage reading, there is a voltage drop across the contacts. The higher the voltage, the worse the drop. The drop is caused by the contacts burning and the conductive surface is not even.
If you find either of these reading above to be true, replace the relay.
Senior User
Joined: Sep 2003
Posts: 156
Likes: 0
From: orygun
i haven't replaced mine, but i priced one....at the dealer here in town they quoted me 96 bucks....an aftermarket dealer in truck parts gave me a price of 87 bucks.... and i believe napa had some for even cheaper than that.
Junior User
Joined: Dec 2002
Posts: 54
Likes: 0
From: Edmonds Washington
I got mine from my local International dealer. it was far cheaper than the above mentioned prices. Dont recall $ exactly. it's a chinch to replace. Just remove the fancy fuel filter cover and there it is.
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Freshman User
Joined: Jun 2003
Posts: 26
Likes: 0
From: Denver, CO.
I bought one last summer for about 60 bucks at the International dealer it is on yop of the engine behind the fuel filter.
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