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2nd Gen Non-Engine/Transmission Does anyone have a LSD in the Front
- Thread starter tpruitt
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Generally, the reason limited slip differentials aren't used in the front is that the truck would strongly resist going around a corner - can you say terminal understeer??!! 
If you need one for off-road applications and still want to keep an open differential for on-road use, I'd suggest an air locker that you can engage or disengage when needed.
Rusty
If you need one for off-road applications and still want to keep an open differential for on-road use, I'd suggest an air locker that you can engage or disengage when needed.
Rusty
What Rusty said. Not to mention the fact that you will be replacing that LSD in a hurry (unless you never turned).
You definitely want to have an open front diff on the street. If you need more traction off-road, try an air locker or that new vacuum shifted diff for D60s that was in an off-road mag a few months back.
hohn
You definitely want to have an open front diff on the street. If you need more traction off-road, try an air locker or that new vacuum shifted diff for D60s that was in an off-road mag a few months back.
hohn
ARB makes excellent lockers. I still prefer detroits, but as far as air lockers go ARB is the answer. It's quite spendy though, might i ask why you need lockers on the front (in my opinion the rear) on a road vehicle? I have a cruiser with locked front and rears, but i tow it to location and crawl the rest. I just can't see the need for a locked front end on a highway pickup.
sled pulling and drag racing it would have advantages, perhaps this is what you're after.
sled pulling and drag racing it would have advantages, perhaps this is what you're after.
I am the pursuit to building an all around truck i will be doing some sled pulling but not a whole lot. There are a bunch or trails around here that i want to start wheeling the truck on. I have a LSD in the rear that is not worth and plus it a whole lot easier to pick a rear wheel up then it is a front that is why i wanted a front. There have been some places that i have gone and picked up the rear wheel and pretty much the only wheal that is pulling is one of the front. An ARB would be the best bet but i have heard they have had some problems with them.
If all around is what you desire ARB is almost the only answer. I would not put a detroit or lockrite in the front if you intend on driving on pavement at all. ARB's aren't the strongest, but they are better then most. The problems aren't as common as one might think, i know several people that have had them and abused them... . this was with much smaller vehicles than a 3/4 ton truck though.
I prefer shortwheel base vehicles for wheeling, long wheel bases just have so many disadvantages. I bet you'll be eating several carrier bearings, better bring spares, and the front suspension design, well it's awful good luck getting that to perform.
The weight of these trucks would be a challenge for the hills, i'd like to watch one but sure wouldn't want it to be mine!
I prefer shortwheel base vehicles for wheeling, long wheel bases just have so many disadvantages. I bet you'll be eating several carrier bearings, better bring spares, and the front suspension design, well it's awful good luck getting that to perform.
The weight of these trucks would be a challenge for the hills, i'd like to watch one but sure wouldn't want it to be mine!
If you retain the center axle disconnect you can only use a selective locker.
Jared
Jared
Yes the ARB or maybe the Eaton E locker? With the front axle disengaged the axles spin through the side gears continually so you need something that fully disengages so the side gears can backspin.
The T Rex system is nice, it does a very good job of turning a 40 mph road into a 80 mph road.
Jared
The T Rex system is nice, it does a very good job of turning a 40 mph road into a 80 mph road.
Jared
what do you mean by the side gears needing to back spin? why do they need to do it?
Assuming you don't have 4. 10 axles ratios, ARBs would be the way to go. ARB doesn't offer anything above 3. 73 for the 35spline Dana 80. As long as you had them installed by a qualified shop, I'm sure ARB would take care of any breakage. A little expensive though, I guessing you'd pay about 2000 in parts and labor I have no idea. I do know they are the most difficult to install and some drivetrain shops won't ever touch em. That is, ones that have done them once before.
BTW, LSD (limited slip diff) / Locker (locking diff)
The above posts are little confusing, someone correct me if I'm wrong. If you put a LSD (clutches and stuff) in the front and are driving it on the street in 2WD there is no power going to the wheels therefore each wheel will spin independantly. (This does not apply to those of you that drive in snow, which I would recomded open diffs). Offroad the LSD up front is not going to pull like a locker and would be very tame IMO. I had a Detroit SL in a Scout II I use to have. With the 4sd manual, it was not bad driving it on the street. If I was under power going around a 90deg turn it would definitly chrip but very liveable. If it was a daily driver I probally would have hated it, and would have had to rotate my tire about every 1000 miles. Plus the power that these Cummins have I hate to have the rear end come around on me on wet curve at 50 mph.
My . 02
BTW, LSD (limited slip diff) / Locker (locking diff)
The above posts are little confusing, someone correct me if I'm wrong. If you put a LSD (clutches and stuff) in the front and are driving it on the street in 2WD there is no power going to the wheels therefore each wheel will spin independantly. (This does not apply to those of you that drive in snow, which I would recomded open diffs). Offroad the LSD up front is not going to pull like a locker and would be very tame IMO. I had a Detroit SL in a Scout II I use to have. With the 4sd manual, it was not bad driving it on the street. If I was under power going around a 90deg turn it would definitly chrip but very liveable. If it was a daily driver I probally would have hated it, and would have had to rotate my tire about every 1000 miles. Plus the power that these Cummins have I hate to have the rear end come around on me on wet curve at 50 mph.
My . 02
Locker / LS
You can use any locker/ LS you want to in our trucks... Here's why:
Your front end has the following components: (listed driver's side to passenger side)
(1) Driver's side tire/wheel, (2) flanged hub, (3) outer axle, (4) u-joint, (5) DS inner axle, (6) differential (including spider gears), (7) PS inner axle (part 1), axle disconnect collar, (8) spud shaft( 2nd half of inner axle), (9) u-joint, (10) outer axle, (11) flanged hub, (12) Pass side tire/wheel.
When you're driving around in 2wd everything from 1 - 6 is turning together (because you don't have the option to unlock your hubs)
On the passenger side parts 8-12 are also turning together (for the same reason, no unlocking hubs)
The only thing that having an open diff does for you is allow one small part, (7, the passenger side inner axle half) to spin at a different rate than the driver's side parts.
If you add an LS, a Detroit locker (or worst case, even a spool) all it does is force the passenger side inner axle half to spin at the same rate as the driver's side inner axle. There will be no binding around corners because the passenger side inner axle is split and will not allow a direct connection between the driver and passenger side wheels… as long as you’re in 2wd
Actually, the Detroit probably won't even lock, since it's activated by torque input from the pinion side of the diff (from the drive shaft)
When you are driving in 2wd your t-case is not sending power through the drive shaft, but it still turns because the driver's side wheel turns it's axle and the diff, which is connected to the drive shaft.
It is true that you might realize some small gains in fuel economy with an open diff because the drive shaft can spin slower than the diff, (but if it does this will force the passenger side inner axle half to spin backwards)... In practice as you accelerate the drive shaft may spool up a little slower than your driver's side wheel axle, etc, but soon it will be spinning right along with everything else.
I have run a Detroits, ARB's, Limited slips, and open diff's in Jeep Wranglers (same Chrysler passenger side axle disconnect system).
A Detroit locker in 2wd is transparent (in our trucks) and causes no driving difficulties (some argue that it's actually better for your gears because it won't wear the ring and pinion with the inner axles spinning at different rates. )
On a side note, the Chrysler system of not using locking hubs causes all of the rotating mass of your axles, u-joints, diff, drive shaft, etc to spin when you drive which causes us to have lower fuel economy than we would if we could simply unlock our hubs! I guess Dodge feels that the convenience of not having to climb out and lock our hubs, (or the reliability of not using auto locking hubs) outweighs the disadvantages in MPG.
Use any locker or LS you want! In 4wd it will work as designed... My $. 02?... An ARB is a waste of your money in a Chrysler product with a two piece axle. An ARB is weaker (components and because of air hole in cap), introduces moisture (from compressed air), and will need servicing sooner (when o-ring goes)
When you unlock the ARB in 2wd all it does is allow that little passenger side inner axle to spin free, (and because of the design of a diff there is no energy savings because between the two axle shafts and the drive shaft something has to turn along with the driver's wheel!)
Oh, one other thing. Our two piece passenger side inner axles are weaker than a one piece axle, and so are our axle housings. If you’re really going to be doing heavy duty stuff I think it’s best to get a one piece axle with locking hubs…
You can use any locker/ LS you want to in our trucks... Here's why:
Your front end has the following components: (listed driver's side to passenger side)
(1) Driver's side tire/wheel, (2) flanged hub, (3) outer axle, (4) u-joint, (5) DS inner axle, (6) differential (including spider gears), (7) PS inner axle (part 1), axle disconnect collar, (8) spud shaft( 2nd half of inner axle), (9) u-joint, (10) outer axle, (11) flanged hub, (12) Pass side tire/wheel.
When you're driving around in 2wd everything from 1 - 6 is turning together (because you don't have the option to unlock your hubs)
On the passenger side parts 8-12 are also turning together (for the same reason, no unlocking hubs)
The only thing that having an open diff does for you is allow one small part, (7, the passenger side inner axle half) to spin at a different rate than the driver's side parts.
If you add an LS, a Detroit locker (or worst case, even a spool) all it does is force the passenger side inner axle half to spin at the same rate as the driver's side inner axle. There will be no binding around corners because the passenger side inner axle is split and will not allow a direct connection between the driver and passenger side wheels… as long as you’re in 2wd
Actually, the Detroit probably won't even lock, since it's activated by torque input from the pinion side of the diff (from the drive shaft)
When you are driving in 2wd your t-case is not sending power through the drive shaft, but it still turns because the driver's side wheel turns it's axle and the diff, which is connected to the drive shaft.
It is true that you might realize some small gains in fuel economy with an open diff because the drive shaft can spin slower than the diff, (but if it does this will force the passenger side inner axle half to spin backwards)... In practice as you accelerate the drive shaft may spool up a little slower than your driver's side wheel axle, etc, but soon it will be spinning right along with everything else.
I have run a Detroits, ARB's, Limited slips, and open diff's in Jeep Wranglers (same Chrysler passenger side axle disconnect system).
A Detroit locker in 2wd is transparent (in our trucks) and causes no driving difficulties (some argue that it's actually better for your gears because it won't wear the ring and pinion with the inner axles spinning at different rates. )
On a side note, the Chrysler system of not using locking hubs causes all of the rotating mass of your axles, u-joints, diff, drive shaft, etc to spin when you drive which causes us to have lower fuel economy than we would if we could simply unlock our hubs! I guess Dodge feels that the convenience of not having to climb out and lock our hubs, (or the reliability of not using auto locking hubs) outweighs the disadvantages in MPG.
Use any locker or LS you want! In 4wd it will work as designed... My $. 02?... An ARB is a waste of your money in a Chrysler product with a two piece axle. An ARB is weaker (components and because of air hole in cap), introduces moisture (from compressed air), and will need servicing sooner (when o-ring goes)
When you unlock the ARB in 2wd all it does is allow that little passenger side inner axle to spin free, (and because of the design of a diff there is no energy savings because between the two axle shafts and the drive shaft something has to turn along with the driver's wheel!)
Oh, one other thing. Our two piece passenger side inner axles are weaker than a one piece axle, and so are our axle housings. If you’re really going to be doing heavy duty stuff I think it’s best to get a one piece axle with locking hubs…
Trey,
Although I'd like to hear from anyone who has a Detriot Elec Locker as well, unfortunatly there is a very limited selection for Dana 80s and the Detriot Elec is not one of them. As far as lockers go I think your choices are a Detroit SL and an ARB 3. 73 and under, and they probally make a spool too, but heck if you want to do that, you can do it really cheap, the "Lincoln Locker", weld your spider and side gears together. This is highly NOT recomended.
Rhickman,
A spool on the frontend is extremly stressful to steering components. Not to mention the frame that your steering box is mounted to. Forget about your current steering radius on the trails. Plan on making four point turns alot. For an offroad vechicle I'd concider put one in the back, just save costs, but it's not worth it in the front.
Although I'd like to hear from anyone who has a Detriot Elec Locker as well, unfortunatly there is a very limited selection for Dana 80s and the Detriot Elec is not one of them. As far as lockers go I think your choices are a Detroit SL and an ARB 3. 73 and under, and they probally make a spool too, but heck if you want to do that, you can do it really cheap, the "Lincoln Locker", weld your spider and side gears together. This is highly NOT recomended.
Rhickman,
A spool on the frontend is extremly stressful to steering components. Not to mention the frame that your steering box is mounted to. Forget about your current steering radius on the trails. Plan on making four point turns alot. For an offroad vechicle I'd concider put one in the back, just save costs, but it's not worth it in the front.
Re-arange the clutch packs in the 80 and you'll be happily surprised at how well it locks.
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Issue 128 – Digital Version
Digital Magazines
FREE!
TDR Test Drive - Digital Edition
Renew
Subscribe
Gift Subscriptions
Back Issues
Subscription Status
Address Change Form
Buyer's Guides
Ram Diagnostic Trouble Codes
The Perfect Collection
The Perfect Collection Vol. II
TSB Updates
Dodge/Cummins Historical Overview
Cameron Collection
What Makes Us Tick?
Product Showcase
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