Alternator replacement
Thread Starter
|
Senior User
Joined: Jun 2012
Posts: 254
Likes: 0
Alternator replacement
Is it safe to assume that my truck is set up for snow plow because it has dual alternators? I think one of my alternators is going bad. On my scangauge i run my truck and the batteries stay pretty constant at around 14 volts. When i run my plow up and down like we do, my voltage drops to 12.0- 12.5 volts and it usually takes a fair amount of driving to get the batteries back up to 14. It seems to me that i am losing an alternator. What do you guys think. I have an 04 F350 6.0L
also what amperage do the stock alternators come at? I figure 110 or 120
also what amperage do the stock alternators come at? I figure 110 or 120
Certified Thread Hijacker
Joined: Aug 2001
Posts: 14,441
Likes: 59
Is it safe to assume that my truck is set up for snow plow because it has dual alternators? I think one of my alternators is going bad. On my scangauge i run my truck and the batteries stay pretty constant at around 14 volts. When i run my plow up and down like we do, my voltage drops to 12.0- 12.5 volts and it usually takes a fair amount of driving to get the batteries back up to 14. It seems to me that i am losing an alternator. What do you guys think. I have an 04 F350 6.0L
also what amperage do the stock alternators come at? I figure 110 or 120
also what amperage do the stock alternators come at? I figure 110 or 120
The upper is a large case 6G alternator and 140 amps, the 4G lower alternator is 120 amps
Josh
Senior User
Joined: Dec 2010
Posts: 158
Likes: 0
I would test both alternators. I have had alternators go out on the dual setup and never show the charging light! I noticed my voltage a bit lower than normal, no light but when testing found my upper alternator was not working. Replaced both even thou the lower showed good. Now voltage is 14.2-14.5 even at idle depending on temperature.
Posting Guru
Joined: Nov 2010
Posts: 1,347
Likes: 0
From: Eagle Mountian, Utah
Brandon I plow with my truck as well. My alt works fine but when the plow is in use it drops the voltage down to roughly 12 volts give or take 2 points. After the voltage drops it takes roughly 15-30 seconds for the voltage to recover to the 13.8 range. And its faster when I rev the motor, takes longer when idleing. It is normal for this to happen. Its like the difference between static and operating water pressure. This is hard on batterys so keep your receipts. And watch for failures or signs of it. My last set of walmart batterys lasted about 18 months. But that was two plow seasons. They have a 3 year full replacement warrenty. And they will replsce both if one has failed. As long as you tell them its for a diesel truck.
Postmaster
Joined: Jan 2005
Posts: 4,424
Likes: 12
From: BC Canada
Definately sounds like you have one or both alternators going out. They get really hot, so individually load testing out of huge truck is paramout. I would replace the upper to a larger alt like my Leece Neville in signature at 230 amps, a new lower 120 will be the backup when the larger one is too hot to produce. I would also advise upgrading all you positive and negative cables to 0/0 or double zero with big ends crimped and soldered and use dielectric grease on all bolts. Those plows pull a lot of juice, bigger cables are needed for the above alternator, it's rated at 230 amps. You also may want to consider switching batteries around once in a while as the passenger side takes all the power form the bigger alternator at least.
Certified Thread Hijacker
Joined: Aug 2001
Posts: 14,441
Likes: 59
Josh
Trending Topics
Thread Starter
|
Senior User
Joined: Jun 2012
Posts: 254
Likes: 0
Thats what ill be goin with probably because of all the things i run in the truck. Just bought two new interstate batteries, probably the best desicion in batteries ive ever made. Thanks gents
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Postmaster
Joined: Jan 2005
Posts: 4,424
Likes: 12
From: BC Canada
The PCM is instructing one or the other alternator to charge, so effectively, you have to upgrade both to get what you are after. I agree upgrade the bottom one, but you also need to do the top, if they load test as not being up to par charge wise.
Mike
Mike
Thread
Thread Starter
Forum
Replies
Last Post
bike_guy123
1999 - 2003 7.3L Power Stroke Diesel
14
Dec 31, 2014 06:26 PM
2003 EXCURSION
6.0L Power Stroke Diesel
5
Jan 23, 2014 07:06 PM