I made the huge mistake of buying my last truck not realizing it didn’t have posi-traction. I have lots of trouble getting stuck in the winter.
It’s a 2006 Dodge 2500 4WD manual transmission. I asked the dealer if it’s possible to change it to Posi. He says no. Something to do with the gear ratios. Mine is 3.73, most posi are 3.55 or something like that, and the transfer case ratio for the the 4WD comes into play as well.
Then he mentioned something about an aftermarket conversion called an air-lock or something like that which might work. Does anyone know anything about this?
Steve
Replies
air locker, detroit lockers, all can be retrofitted, get a 4x4 magazine and read up all the ads, call a few and ask, the ring gear carrier needs to be changed usually, then the ring and pinoion depth reset, can be costly, and need a person who has a clue doing it. may be better looiknbg for a used rear w/ righ gears from a salvage yard that has the loking diff already.
dave
I think you would be better off just trading your whole rear axle assembly with a salvage yard for a posi unit of the correct ratio if that is a possibility.
I don't think Dodge has the same setup as GM. I believe the Dodge is a typical posi unit and doesn't actually lock up both axles.
The conversion kits do lock both axles.
Either way, that was an expensive mistake, and I know what you are talking about because I did the same thing on my first 4wd truck.
Edited 1/8/2009 12:44 pm ET by BoJangles
ARB air lockers
http://www.arbusa.com/Products/Air-Lockers/10.aspx
I have ARBs front and rear in my Jeep. Let me tell you, you don't want to use them in the snow. Definitely not the front ever on road and not even the rear alone, unless you are off the road already. Off road however they rock. Careful with the lunch box locker as well in snow. Unpredictable results when they lock and unlock. The posis usually wear out after 50K miles or so as they are done with clutch packs usually.
That's right....those things are not made for the road.
Well, the truck was dirt cheap. I've been looking into just getting a new truck for a variety of reasons, but I actually got a better deal on the 06 in dec of 05 than I've been able to scare up on an 08 now. Hard to believe.Steve
Steve, I gave up and bought a used truck. I can't believe the dealers around here act like there is no problem selling vehicles.
I shopped Ford, Chevy, Dodge. Spent a good deal of time at each dealer, and made it plain that I was buying if the price was right. I had to pester them for follow up. Still the prices are higher than they were last time I bought, plus nobody would give me diddly for trade-in. Ford even said flat out, we don't want your trade.My truck only has 42K on it, so I don't see the point in a used one for my circumstances. I was having electrical problems that they couldn't seem to pin down, but somehow they managed to get fixed as soon as it went out of warranty. Been a good truck otherwise. So now I'm less eager for a new one. The lack of Posi is really annoying me though.Steve
Edited 1/8/2009 2:36 pm by mmoogie
I had the same experience. I really didn't need a truck, own Jeep and Rav4 already, but wanted one.
I had the same experience at the dealers I went to. The HUGE place was the worst!
I called and emailed dealers in Syracuse and they were blase about dealing. I wonder about the news.
Not to mention only being able to leave (1) one black line when pulling away from the traffic light. What color are your panties.
I have aussie lockers in mine, installed them myself, simple
I thought ARB was from AustraliaAgain, you want traction off road, they make two spools of your diffs. Unstoppable off road but really bad on road if you engage on road.
Edited 1/9/2009 12:55 am by rjgogo
yes, but Aussie lockers are a complete different company, nothing to do with arb
I would stay away from an Detroit Locker because you may not like the way it drives. I had a Eaton Detroit Locker in a 4x4 truck I owned several years ago and thought is was great for off-road driving but not really the best option for something you plan to drive on the street on a regular basis. If you are wanting a "mechanically locking" differential, I think that your best option would be the Air Locker. Having the ability to turn it off and on is a big plus. But, you would probably be happier with an aftermarket limited slip like the Eaton Detroit "Trutrac". I check Summit Racing and it looks like that make one that will fit your truck - I'm no expert though.
There are probably other options - this was just what I came up with first. If you have a local offroad shop it might be worth giving them a call.
Steve
Thanks. That "truetrac" looks like just the thing. Plus it's a lot less expensive than the air lockers. I'm getting some conflicting information about the axle from the dealer versus what the web site says is the right unit for my vehicle though. Will have to run that to ground...Steve
As long as you don't want to turn corners, you can just pop off the cover and hit it with the welder.
I've always wondered, exactly WHAT gets welded in the rear end ?I need an explanation with pictures.
"WHAT gets welded in the rear end "Please this is a PG rated forum..
William the Geezer, the sequel to Billy the Kid - Shoe
You weld the spider gears. Turns the diff into a spoolHere are your pictureshttp://images.google.com/images?hl=en&q=welded%20spider%20gears&um=1ie=UTF-8&sa=Ntab=wiYou can also do a search on Lincoln Lockers. You know Lincoln, not good old Abe but the popular maker of the tombstone welder.
Edited 1/9/2009 1:09 am by rjgogo
Thank you.
http://justdifferentials.com/
Thanks! That looks like the go-to-place.
I understand your problem but before you mod your drive train look into better tires.
My F150 had Goodyears and I never had good traction in the wet, My PT cruiser Goodyears and same problem, I now have a Sebring with Goodyears and no wet traction.
Changed the F150 to Continentals and its a world better and the F150 has a Posi rear. Sebring is next! tirerack.com is a good place to check for reviews.
That's a very good point. I changed to Firestones and they are much better than any tire I've ever had on the trucks.
Better traction and better wear.
you'r dealer is lost any auto part's store can fix you up and there are more options then ARB air lockers.that said ARB lockers can be installed in both front and back ,as you hit bad snow,mud,ice you push a button and it starts a small air compeser and it lock both front and back or you could just lock the back.i have this in my truck and it work great.best of all when get out of the bad situation you turn them off and you no longer have the added wear and tear that you would from a true locker.ARB is well know in the 4wheel drive off road play ground of rock crawling and such.there web site will get you to a close by dealer.good luck
Here's my $.02 again. Actually it's more like $2.
1) If you're looking at tires, BFG A/T are a home run. Outstanding dry/wet/snow traction, quiet, wear like iron.
2) Posi or no has NOTHING to do with what ratio is in the rear or the transfer case. That's the dealer's way of saying they don't have a clue. Your truck probably only came equipped with the factory posi with that ratio, because it was a multi-part towing or traction package. It has 0 to do with what will work.
3) Lockers are generally a little rough to live with, except auto lockers like the Powertrax. Posis are there all day, every day, and can have their own drawbacks.
During normal conditions, the rear wheels need to be able to turn different speeds around turns, and the open(spider-gear) differential allows this and still allows torque transmission. Unfortunately, if one wheel breaks traction it just spins away and all torque is lost through that rotation.
A posi adds mechanical drag to the wheels turning different speeds, so if one breaks traction some torque is still applied to the other wheel. The good: very smooth, and always on -operator friendly. The bad: It's always on, and instead of spinning one wheel on wet roads, you're sideways, and requires replacement of entire carrier. The detroit True-Trac does this with helical gears instead of wearable plates or cones, and is excellent.
A locker mechanically locks the axles together, doing everything a posi does but better...and worse. Also requires replacement of complete carrier. Edit: They also usually engage/disengage harshly.
A selectable locker is one that you decide when to engage, and is operated either electrically or by air pressure. The good: no locker when you don't want it. The bad: air lockers are expensive, complex(requires onboard compressor, etc) and notoriously unreliable, and the electrics aren't cheap either.
Finally, auto-lockers like the Powertrax/Lock-Right are a compromise between posi and locker. In normal conditions, it's a plain old open differential. Under load, they lock. They engage only under load, so if you hit ice they disengage themselves. They are available for most axles, and fit into the existing carrier after you remove the spider gears(carrier and gears stay in the truck, they take about 1-1.5hrs to install).
If you take a look under your truck, you can usually ID the axle by the shape of the diff cover. Your truck probably has an AAM 10.5 or 11.5 rear axle, but I can't see it from here. :) If it's got the Allison trans, it's most likely the 11.5.
Oh, 1 more thing. When replacing the entire carrier, there is no need for a complete ring and pinion setup -because the pinion to carrier centerline distance has not changed. It's just a matter of setting the backlash(easy).
Edited 1/10/2009 12:25 am by deadman1
Posi or no has NOTHING to do with what ratio is in the rear or the transfer case. That's the dealer's way of saying they don't have a clue. Your truck probably only came equipped with the factory posi with that ratio, because it was a multi-part towing or traction package. It has 0 to do with what will work.
What??? I'm sure that what the dealer told him was that the front axle drive ratio must match the rear axle drive ratio.
You can't just throw any rear end ratio you want into a four wheel drive vehicle. If the front and rear aren't the same, you will snap a few critical pieces in half.
Thanks for all the helpful information everyone.Yes, part of my problem is highway tires with 40K miles on them. They were passable for the first couple of winters, but not cutting it this year. So new Bridgestone Dueler A/T Revos are en-route as we speak from Tirerack.com. As an aside...I like to try and give my local merchants a stab at coming close to online or big-box prices on stuff, and will pay a little more for things locally if they will make an effort to meet me at least halfway. So I called the the tire dealer and asked if he wanted to take a stab at it, and he said sure, got the OK from corporate, only to find the tires I wanted were on back order, and they had no idea how long it would take for them to get them. So they will be on my doorstep from Tirerack on Monday.There is no Eaton Detroit Locker Truetrac for my 10.5" 14-bolt, but there is a an American Axle OEM helical posi unit at that web site BossHog posted for $575. I'm thinking I'll probably go that way. Any idea what it'll cost to have a speed shop install that?The Air lockers cost nearly 1000 dollars, and are more than I really need. I just want brainless and dependable. My previous dodge 1500 with posi and decent tires never got stuck. I could drive out of just about anything. That's all I'm after.Steve
There is no Eaton Detroit Locker Truetrac for my 10.5" 14-bolt, but there is a an American Axle OEM helical posi unit at that web site BossHog posted for $575. I'm thinking I'll probably go that way. Any idea what it'll cost to have a speed shop install that?
I'd figure about 3 hours x labor rate, + fluid, silicone, and likely carrier bearings as well. Theoretically you can re-use the carrier bearings, but they're a pain to remove without damaging them, and at $40-50 each I just replace them.
EDIT: Just a quick check, dodge carrier(side) bearings for your 10.5 are $25 each.
Edited 1/10/2009 12:43 pm by deadman1
Posi or no has NOTHING to do with what ratio is in the rear or the transfer case. That's the dealer's way of saying they don't have a clue. Your truck probably only came equipped with the factory posi with that ratio, because it was a multi-part towing or traction package. It has 0 to do with what will work.
What??? I'm sure that what the dealer told him was that the front axle drive ratio must match the rear axle drive ratio.
You can't just throw any rear end ratio you want into a four wheel drive vehicle. If the front and rear aren't the same, you will snap a few critical pieces in half.
What??? LOL
Whoa, slow down and actually read the posts you're commenting on before you start lecturing me (EDIT: ...on automotive matters. On building, I could always use some lecturing). That's NOT what I said, nor is it what HE said his dealer said.
Edited 1/10/2009 11:55 am by deadman1
on some carrier, if you go too big on the gears, the edge of the gear will hit the locker, so there is a need to either change the gear ratio or to a different carrier.. it not a big deal most people just change the carrier. on a detriot eaton and other the carrier is replace anyway, it depends on the actual size of the ring gear. Ratio has nothing to do with it
on some carrier, if you go too big on the gears, the edge of the gear will hit the locker, so there is a need to either change the gear ratio or to a different carrier.. it not a big deal most people just change the carrier. on a detriot eaton and other the carrier is replace anyway, it depends on the actual size of the ring gear. Ratio has nothing to do with it
Yep, pretty much.
The ratio determines the actual physical ring gear and pinion size within the parameters of the axle size(8.75, 10.5, 11.5, etc), but the carriers/posis are offered to fit different ratios, so it's just a matter of selecting the correct one for the ratio you have.
At any rate, we're in agreement that having a particular ratio does not preclude installing a posi or locker in it.
What I'm telling you is that.....that's probably what the dealer told him and the OP is the guy who didn't understand the whole thing...probably not enough to clear it up with the dealer. The dealer knew the front and rear ratios had to be matched and that you couldn't just throw any rear end ratio in there for the heck of it.
You assume the dealer is an idiot. I assume he knows what he's talking about and the poster didn't quite understand him.
I think you should have explained the facts to the OP, instead of telling him the dealer was a bozo. No offense to you, but you didn't really help the poor guy much.
Look dude, the OP was pretty clear in what he stated.
He asked the dealer about putting in a posi, the dealer is the one that brought up ratios, because he has no concept that you can put a different carrier in a rear. All he knows is that the factory parts guide says he can order a replacement posi, but that it came with a different ratio, and the rest is just barking up the wrong tree to start with.
I spent the better part of 10 years as a dealer tech, the last 7 of which as a dealer master tech. Dealer techs, service advisors, service managers, parts managers 99% of the time have no idea about anything that is not factory equipment...and only from the manufacturer they are working for. 99% of the time, they cannot think outside the box -that's not their expertise and experience, and most techs period get the what-fits-what, but not the why. Forget parts and mgmt. The general philosophy in dealerships is that if it's not factory equipment, it's no good.
There are -thank god- exceptions to this, but I've seen this scenario played out hundreds of times.
You're entitled to your opinion as to the usefullness of my post.
I actually: Still think I read his correctly, and If anything posted too much info.
Edited 1/10/2009 3:28 pm by deadman1
Well....he told you what he has in his truck. Instead of blasting off at how dumb you thought the dealer was, why didn't you look up some information and say "here's the particular unit I would recommend for your situation" ? Now that would have been more helpful!
BTW, does anyone make a unit that will convert modern, standard four wheel drive front hubs, to manual locking/unlocking front hubs? Or is that impossible? There is so much more wear and tear on front ends, not to mention wasted fuel, caused by not being able to disengage the front hubs like in "the old days".
Well....he told you what he has in his truck. Instead of blasting off at how dumb you thought the dealer was, why didn't you look up some information and say "here's the particular unit I would recommend for your situation" ? Now that would have been more helpful!
Oh for christ's sake, let it go.
#1 All he gave was year and model, not axle size and ratio.
#2 I gave him more than enough info to make his own decision based on his needs, as well as my opinions of the various options.
If he had come back with more info, and perhaps said he was leaning towards a locker, which one do you recommend, I would have gladly obliged.
BTW, does anyone make a unit that will convert modern, standard four wheel drive front hubs, to manual locking/unlocking front hubs? Or is that impossible? There is so much more wear and tear on front ends, not to mention wasted fuel, caused by not being able to disengage the front hubs like in "the old days".
Yes. Year, make, model?
GM / Chevy Pickups ....2500 series......Models since 2005.......don't want a part#, just an idea where to look.
Bad news/good news: There is none/you don't have to!
The late chevys are using an independant front axle comprised of cv shafts and stub shafts, that spline into the spider gears inside a pumkin in the center.
When you select 2wd, 2 things happen. 1) the xfer case stops driving the front driveshaft, and 2) the actuator in the front pumpkin disconnects the pass side axle in the pumpkin. The drv side axle just spins the spider gears inside the carrier, and the carrier, ring, pinion and front driveshaft stop tuning.
On top of that, there really is no way to disconnect the front wheel from their cv shafts, and even if you could...gains would be negligible since they're only spinning the cv shafts and spider gears anyway.
Early in GM IFS, they were using a thermal front axle actuator that was problematic, but your 2005 should have an electric unit.
Edited 1/10/2009 5:25 pm by deadman1
We have a 1995 Chevy 2500 work truck. It has about 100k on it now and runs like a top. The only costly problem we have with it is that it eats front axle seals like clockwork....every 20,000 miles since the day it was born.
Axle seal is $6.00.....labor to change seals on both sides, around $350. We have not had that problem yet on the newer trucks, but those haven't been run that much yet.
I'm more concerned about the constant maintenance than the savings in gas, but I'm sure that adds up too.
The '95 has a thermal actuator and you are right, it is a PITA!
We have a 1995 Chevy 2500 work truck. It has about 100k on it now and runs like a top. The only costly problem we have with it is that it eats front axle seals like clockwork....every 20,000 miles since the day it was born.
Axle seal is $6.00.....labor to change seals on both sides, around $350. We have not had that problem yet on the newer trucks, but those haven't been run that much yet.
I'm more concerned about the constant maintenance than the savings in gas, but I'm sure that adds up too.
The '95 has a thermal actuator and you are right, it is a PITA!
Wow! every 20k? Yeesh...that's crazy.
High sand/dust conditions maybe? If there's no unusual operating environment, I'd be seriously looking at a) the vent for plugging, b) the stubs that the seals ride on for damage, and c) there are fine roller bearings that can wear and allow the stubs to move around.
The only thing is, all of those would likely leak alot sooner than 20k... are they being replaced with GM seals or ? For $6 ea, I doubt it.
GM upgraded the seals in the late 90's for the s-10 series trucks and I think the fullsize also. It's a much better design, and they also do offer an upgraded electric front axle actuator that retrofits into your axle. -No more slooooow engagement in cold weather.
When I first brought the truck into the dealer at 20k for warranty work on the axle seals, I asked them if this was some kind of freak occurance, because I had never heard of such a thing before.
The mechanic said, " I'll see you at 40k," and he was right.
All GM parts and work. No unusual driving conditions. Apparently just a poor design that was peculiar to a few years.
When I first brought the truck into the dealer at 20k for warranty work on the axle seals, I asked them if this was some kind of freak occurance, because I had never heard of such a thing before.
The mechanic said, " I'll see you at 40k," and he was right.
All GM parts and work. No unusual driving conditions. Apparently just a poor design that was peculiar to a few years.
Yeah, it's pretty common. I know they went to and upgraded 2-piece seal for the s-10s, but I don't recall the fullsize changes...maybe an oil deflector behind the seal...
Anyways, 20k still sounds too frequent. Y'know, they generally are a bit weepy...not a dripping, losing large amounts of fluid leaky, but weepy. Also, the vent for that pumpkin is directly over the driver's side seal...seen more than a few disconnected/cracked/poorly clamped vent hoses dripping onto the seal area...looking just like a bad seal. Normally the hose is routed up and is clipped into the fan shroud way up at the top of the radiator. There's a vented cap on it...make sure it's breathing.
If anything, it's usually the passenger side seal that starts leaking first, and alot of times it's due to the needle bearing in the extension tube being worn.
If you're so inclined, reach under there and try to move the CV flange around. It should/may move in and out a teeny bit, but it should not have any side play at all.
Thanks, I'll check that stuff. I've got a nice,warm shop and it's going to be -10 or worse most of the week.
Again, I appreciate all the useful information from everyone.I'm sorry I wasn't clearer in my original post. I usually am too wordy in my initial posts about things, and I think it sometimes is better to throw out a brief description and wait for some discourse to further the discussion.I dind't know much about the topic before I started looking into it, so I was intentionally a little vague.The service manager did indeed say that what mattered was that the front and the rear have the same ratio. That I understood. He then said that the factory posi setups were on 3.55 ratio setups, only available on the "Power Wagon" package, and not an option at all on my model, at which point a tech walked by and said he was wrong, posi was always an option available on any model. I think the service manager was confusing locking differentials, which may indeed have been an option on the power wagon package, with limited-slip differentials.In any event, he thought it would be hard to find one for a 3.73 rear end in a junk yard that had posi in it though, and that there was no factory upgrade I could get for it. He suggested air-lockers as an alternative. So I came to the experts here for help, which you've all very graciously provided, and I thank you for it.I eventually determined that my rear end is a chrysler 10.5" 14-bolt unit. AAM makes an oem helical-gear posi unit for it for 575 bucks. I just have to find a good mechanic to do the install for me.I'm not a gear-head. I used to work on my own cars when I was a kid, but I no longer have any interest in doing this stuff myself. The most extensive thing I've done was a clutch replacement on my 69 AMX, but that was over 30 years ago. I came to the conclusion many years ago that I was better served by leaving it to people who knew what they were doing and had the tools and facilities to get it done with a minimum of down time on the vehicle. Thanks again,Steve
what the dealer did not tell you was the axel ratio does not matter, you can put a locker in any axle and that is that .........a locker is nothing more then spings and cogs that mash together and spin both tires.the gearing does not matter enless toy go to bigger tires.any shop thet works on 4/4s can set you up in 3 to4 hours and it sould cost about 500.00 to 750.00 depending on the type,a air locker or machanical one the differance is the air one you can shut off and have limited slip that it.
No problem Steve, and thanks for clarifying. Yes, the Power Wagon model included front and rear selectable electric lockers from the factory. IIRC, there was a difference with the axle shafts used in the factory setup too, so just dropping the e-locker in from a PW wasn't quite that simple.
You can see where I was going with the general inexperience/inability to think beyond what was a factory option, or factory based. To them, it's either in the factory parts book, or in a junk yard truck that matches yours. The factory only offered this with that ratio, so that's all there is. Of course the F and R ratios must match, but that's only a concern if you're changing them...which you don't have to, to start with!
There are a multitude of choices available outside that box.
Air lockers are nothing but trouble. ARB buys lots of ad space in the 4wd mags, and sponsors 4wd events, so they get lots of press and look sexy in the magazines.
That AAM helical posi/locker you've picked is identical to the Eaton/Detroit Truetrac, and I strongly suspect they are related. Detroit developed/owned that design a long time ago.
At any rate, it's an excellent piece. Very heavy duty, and gives you the best of both worlds in that it's as smooth as a posi, yet it almost locks totally up like a locker. It also doesn't require posi additives in the fluid, and has no clutches/cones to wear out.
I just know you'll like it.
The closest shop to you I could recommend is OK 4wd in Washington Twp, NJ. I don't know anybody closer to you, but it's a relatively easy job. Your local 4wd or transmission shops are the best bet.
If I still owned a speed/4wd shop in Newton NJ, I'd do it myself!
I installed a limited slip in my first 4 x 4, 1974 Chev, 350 auto, full time . 3.73 Then I got another truck , 1983 F250 460 4 sd. 3.54, The chev would go in 2 wd, where the Ford would have trouble in 4 x, rear end broke, I got limited slip for it ( Dana 60 "U", light duty 1 ton) was hard to find but got used one. ( Rider Racing, Randy' s Ring and Pinon, could supply but US $ put the price out of reach for this Canuck) Like night and day can't count on the times that I didn't need to go to 4 x . Current truck, 1995 GMC 4x4 6.5 Diesel has 3.73 Limited slip. I would never get a truck without Limited slip. Only down side, got to watch how you power into a turn, truck wants to go straight ! ( don't ask how I know, lol )
I would second the suggestion of better tires.
I had a 2wd Ford F250 and I never got stuck in snow with a set of Michelin LTX AT tires on it.
I also had (later) a 03 Astro van with factory posi and never got stuck- but the van had a few hundred pounds of shelving and stuff above the rear axle at all times. Never noticed any odd handling with the posi in rain or snow.
Something not mentioned so far is tire diameters. If you have a clutch type posi unit and the tires on each side are not the same OD, you will fry the clutches. Fastest way to do this is to have a flat and put the spare on... probaly fun with a locker, too.
Snow tires really work- unfortunately you need the space for 2 sets of rims/tires.
I just read your post, haven't read all the responses, so sorry if someone already suggested this. I had a 2 wheel drive Chevy without positraction. I installed a powertrax and traction was much better. I understand that they are now owned by Richmond Gear.
If you google "powertrax" you can probably find their site. Last time I looked at it they had videos of trucks comparing standard differentials with their unit. I can say from experience that their unit works very well.