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Old Jun 29, 2018 | 12:23 PM
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Rear diff opinions

Hey all

03 with 4WD. Harsh Canadian winters, frequent temps of -35c for extended periods of time.

When I drive on an icy road, any bit of wheel spin will make the Ex turn sideways. This can be LIFE THREATENING if you are on an icy or snowy road at -35c. I am wondering what diff options are out there to help with this?

Family member has an 08 Duramax long bed, and the same roads his truck will spin, but track down the road perfectly straight.

Is my LS diff just worn out? Is there a better option? Yes I run studded winter tires too. This will happen to a much lesser degree in 4WD, but in 2WD it can send you flying straight sideways in an 8000lb vehicle.

Thanks for any help
 
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Old Jun 29, 2018 | 03:02 PM
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Are you sure you have Limited slip? I drove my Excursion Back in Ohio (not at -35 but we would hit -20) and never had that issue unless it was black ice. I think it kicks in at 100 rpm difference but when Jacked up in neutral both rear tires spun the same way.
 
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Old Jun 29, 2018 | 03:26 PM
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If you have a limited slip for sure, get it checked out. The clutch may be worn, or the friction properties of the fluid may have just worn out. When was the fluid changed last? In any case, having it checked and repaired means the fluid gets changed. If it's not a limited slip, consider a Detroit TruTrack.

Detroit TruTrack Webpage

Ford 10.5 Trac Lok Limited Slip Clutch Kit
 
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Old Jul 1, 2018 | 01:09 AM
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A worn out LS or an open diff should make it side slide less than a good tight LS. If it's an open diff one tire might spin under power, but it won't try to spin both and spinning both is what will send it sideways. I see no good reason to not always be using 4wd in those conditions, just plain dumb to not take advantage of it. You're much less likely to slip the rears in 4wd and even if the rear does step out on you having the fronts pull you in the steered direction can help tremendously. 4wd also helps with braking, even with ABS.
 
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Old Jul 1, 2018 | 07:20 AM
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Originally Posted by '88 E-350
4wd also helps with braking, even with ABS.

Not sure about that (not trying to be a troll, but willing to learn something new); can you share an example?
 
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Old Jul 1, 2018 | 09:15 AM
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Originally Posted by '88 E-350
A worn out LS or an open diff should make it side slide less than a good tight LS. If it's an open diff one tire might spin under power, but it won't try to spin both and spinning both is what will send it sideways. .

Agreed, Sounds like his LS is working as it should.

I say it all the time, full time lockers or LS suck in the snow.
Sure there are brief moments where having both wheels powered is a huge advantage and that is why a selectable locker is best suited to snow conditions.
 
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Old Jul 1, 2018 | 09:12 PM
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It was a hot one today and just a few days ago my AC stopped coming out of the vents and only c9mijg out the defrost. I started trying to track down a vacuum leak and after asking a friend, he told me most likely it was the vacuum pump itself.

Looks like I will be grabbing one of those before we leave for Texas Tuesday night. Not having AC down there would really suck.
 
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Old Jul 2, 2018 | 01:36 PM
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Originally Posted by Twitchyleprechaun
It was a hot one today and just a few days ago my AC stopped coming out of the vents and only c9mijg out the defrost. I started trying to track down a vacuum leak and after asking a friend, he told me most likely it was the vacuum pump itself.

Looks like I will be grabbing one of those before we leave for Texas Tuesday night. Not having AC down there would really suck.
I had the same issue and recently replaced the vacuum pump, hoses from the fenderwell bracket to hubs and 4wd solenoid behind the passenger battery and it fixed the issue. If your vacuum pump runs and runs and never shuts off it’s most likely a leak and the pump can’t build vacuum so it ends up burning the pump up. After the key it turned my new pump runs about 1 minute 10 seconds before shutting off. I timed it to helo a fellow member diagnose his issue.
 
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Old Jul 9, 2018 | 12:27 PM
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Originally Posted by wpnaes
Not sure about that (not trying to be a troll, but willing to learn something new); can you share an example?
If the front tires have mechanical drag from being in 4wd, this helps slow you down in the ice/snow. Dont know if Im explaining it right but I know what he means.
 
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Old Jul 9, 2018 | 12:28 PM
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Thanks all. Doing diff service this summer so will check it out then. Selectable rear locker sure would be nice!
 
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Old Jul 9, 2018 | 01:25 PM
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I just installed a trutrac on mine, and I am a really happy with it driving around on muddy jobsites so far
 
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Old Jul 10, 2018 | 08:50 PM
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I agree that your limited slip is probably working as it should. Any type of locker or limited slip will make it seem like your rear end is sliding out from under you when your spinning on ice. Best thing you could do is invest in some quality winter tires. I’d personally still rather have a limited slip than a open diff. I’ve owned both and I live in Canada. Good luck and be safe
 
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