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Old 10-21-2014, 08:34 PM   #1
aris_unlimited
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true 4wd?

I have a 72 gmc 2500 4th with Dana 60 rear and Dana 44 front. Just curious if these would each have a limited slip meaning that all 4 wheels will turn should I need them too?
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Old 10-21-2014, 08:49 PM   #2
Mike C
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Re: true 4wd?

What does your SPID say?

All 4 will turn and put power down as long as they have approximately equal traction. With open differentials the tire with the LEAST traction gets all the power. But to answer your question you will have to do a little more due diligence...

Rear limited slips or even lockers in the 20 series trucks aren't uncommon. Limited slip fronts were optional but pretty unusual. No way to answer that question on the interwebs with insufficient info provided...
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Old 10-21-2014, 09:14 PM   #3
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Re: true 4wd?

So it wasn't a standard equipment thing? I'm gonna have to crawl under there lol.
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Old 10-21-2014, 09:18 PM   #4
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Re: true 4wd?

Agree with Mike C. Limited slip in the rear end is not uncommon. Limited slip in the front end is less common. It was not a standard thing, it would have been an option and listed in the SPID if factory installed.
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Old 10-21-2014, 10:28 PM   #5
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Re: true 4wd?

All 4 wheels should pull in slippery conditions if you ride the brake a bit while giving it gas...
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Old 10-21-2014, 11:27 PM   #6
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Re: true 4wd?

Quote:
Originally Posted by franken View Post
All 4 wheels should pull in slippery conditions if you ride the brake a bit while giving it gas...

Old farmers trick. I have done that and it has actually worked a few times.
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Old 10-22-2014, 12:29 AM   #7
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Re: true 4wd?

That's exactly how a lot of the modern traction control systems work. The abs applies brake pressure to the wheel with less traction giving the wheel with traction power....
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Old 10-22-2014, 07:17 AM   #8
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Re: true 4wd?

Buy some gaskets and pull the covers. Pretty easy to see if you have open differentials or positraction and the added advantage is that you change out what is most likely decades old gear oil and the covers get some new gaskets.
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Old 10-22-2014, 08:54 AM   #9
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Re: true 4wd?

Actually, open front and rear differentials is "true" 4wd. Front and rear posi is "better" 4wd
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Old 10-24-2014, 02:44 AM   #10
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Re: true 4wd?

I checked the codes in my glove box, turns out I have a rear limited slip or power loc, nothing to note on the front other than the locking hubs lol.

Now to decide if I want to stick with the power loc, which if I remember correctly is a clutch type or switch to helical (I like the lack of maintenance).
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Old 10-24-2014, 08:39 AM   #11
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Re: true 4wd?

Where I live, helical suck for off road. Deep soft sand is not it's friend.

Power locs are great. The more load the tighter the clutches hold.
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Old 10-24-2014, 09:11 AM   #12
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Re: true 4wd?

I have wanted to do this ever since I parted out a 68 GMC 2wd that had a Dana 44 rear with 3.54 posi. These gears installed in a front Dana axle along with the Dana 60 posi 3.54 I have in 8 and 6 lug I have would make a nice 4x4.
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Old 10-25-2014, 01:43 AM   #13
aris_unlimited
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Re: true 4wd?

Quote:
Originally Posted by Bigdav160 View Post
Where I live, helical suck for off road. Deep soft sand is not it's friend.

Power locs are great. The more load the tighter the clutches hold.
Not really that sandy in the areas I frequent out here. Mostly dirt, snow at the right time of year, and rarely mud. I was thinking about front and rear lockers. Could just use an auto locker in the front as it wouldn't matter til I engaged the hubs. Torn on what I would use in the rear as I don't like the idea of drilling holes in the case for an air line, electric line, etc. But I also understand that auto lockers tend to be harsher on road. Maybe a limited slip in the rear and an auto locker up front...

The one reason I don't like the idea of clutch type lsd's is that they occasionally need rebuilding, whereas the helical type are less maintenance.
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