Advice Needed - posi or locker?

[warmblood58]

I have decided to add either a locker or posi to the rear diff on my '94 e350 7.3 IDI. I was told by a friend who worked for Ford that I should consider pulling the carrier and slipping in a posi carrier vs. adding a locker - is it really that easy -I have a Dana 33 rear end -thanks

 

[bobracing]

Yes and no.
A "lunch box" locker replaces the spider gears and is as easy as pulling the cover and dropping the spiders, and replacing with a "lunch box" locker. Some require actually pulling the carrier and ring gear but no gear setup. This type of locker is usually a little harsh in lock up and you WILL hear and feel it.

A posi or full case locker will replace the carrier and require a new gear setup. I don't believe there is a "lunch box" posi.

My personal opinion, is if the van doesn't see dirt, spend the money and put a Truetrac (or other posi) in it. The actual "lockers" aren't overly street friendly and will throw a rig around pretty good. Yes, they can be used but a posi will do most of what a "average" person will ask of it and won't hardly know it's there.

 

[RLDSL]

You can swap out a carrier with minimal setup required, all you need is a dial indicator with a magnet base and a shim set ( or if the dana is screw adjustable, dont even need that) When changing out the carrier you dont alter the pinion depth so all you need to adjust is the lash, which is VERY easy to do. so if you want to go shopping for any kind of replacement carrier you want and just swap your ring rear on it( get a new set of bearings, if you buy from a good gear shop like Randys, you can buy and have the bearings pressed on before delivery so you dont have to fool with it )
If youi get a clutch posi, make sure to use synthetic to make the clutches last or you will have an open diff in 50k miles, True tracs arent as picky , Lockers wont care either way ( but any rear will benefit from reduced friction and better fuel mileage with a high end synthetic )

 

[Ataylor]

I have a true-trac in the Sterling on my 1987 F350. It has worked great for my truck, but I'm not doing any hard core wheelin in a crew cab long bed. It was pricey, but I had it installed when my pinion bearing got sloppy, so it wasn't as much labor since the shop had the differential apart already.

Archie

 

[GOOSE]

I am a fan of the Detroit Locker. They are bulletproof and offer 100% torque transfer to both wheels. If one wheel is on ice and the other on gravel, you will get both to spin. The downside is street manners. Many complain but I put about 80,000 miles on an old truck of mine with one in it and had no issues that bothered me. The biggest thing to watch is going sideways in the rain when the tires spin but a good posi will have this tendency as well.

Considering the money spent to do a carrier transplant, going right to the locker was a logical choice to me. I would have been upset to have put in a posi and been disappointed in it.

 

[riotwarrior]

Completely depends on driving.

What do you want out of the traction aid? Why do you want a traction aid?

What do you do with your vehicle, all street, camping and lots of back road (rough fire roads etc) but no serious OFF road...IMHO

help us understand these answers and then one can help you better...

BTW...no Dana 33 rear diff in a van with a diesel....IIRC there is NO dana 33 diff what so ever.

If anything you have either a Dana 60 or Dana 61 or Sterling 10.25

IMHO though requiring slightly more work, a posi for average joe best bet...if you do OFF road and need 100 % axle lockup off road then a locker, and for that with a D60 or such I'd add a lunchbox locker...

JM2CW

 

[warmblood58]

Thanks! I believe I identified that I had Dana 33 off the ID tag - will check again. I foresee rough fire roads sometimes but the majority of the time on the road. I wanted to do a Ujoint 4x conversion kit but that will have to wait but 4x is one of those things that when you need it, well you need it or a winch/high lift jack etc. I like to ski and 4x is great in snow of course but basically, doing a camper build and want al least some traction device better than one spinning wheel - thank you for the great questions!

 

[riotwarrior]

IMHO a good truetrac or helical gear posi is the way to go for what you are describing, Lockers are great don't get me wrong, but you better understand that they can be noisy on the street, clatter and chirp tyres and adversyly affect handling. You mention skiing...well lockers will put you in a ditch as quick as get you out of one too...

because of the crown of the road you will slip towards the ditch when trying to take off from a stand still...then if you get in a ditch...one wheel with traction and you could be out too... bitter/sweet lockers are..

Posi's are more forgiving, but if tight enough can do very similar actions as a full locker, sliding and such but less chirp on corners and so forth.

I had one wheel on my rear axle off the ground at my mail box no less......and I had to lock in hubs, cause my posi wouldn't drive me forward, even with me using the park brake to try to stop the wheel in the air...I just had NO go...

I'll be installing lockers front and rear...

ONE OPTION NOT DISCUSSED...Selectable locker EG a ARB air locker or the ZIP locker or Elocker

All of these are open diff IIRC and lock axles on demand for ultimate traction, maybe you want to consider this option, though pricey...it does offer a double standard...open/locked!

Al

 

[warmblood58]

Hey, thank you and a ARB was what I was originally thinking - expensive but easy enough for a shadetree mechanic to install? Thanks again, I prefer standard drive but having the option to lock an extra axle to assist traction would be helpful -

 

[hesutton]

I will throw a second vote (or is it the thrid....) for a Detroit TrueTrac helical gear limited slip. Love mine in the F250.. Higher bias ratio than cone/clutch LS's, no "friction modifier" is needed in the gear lube, and no clutches to replace. Would highly recommend it. I will replace the factory LS in my F350 crew cab with one when it gives up the ghost.

Heath

 

[RLDSL]

If you plan on doing a lot of skiing and will be in snow zone a lot during winter, your absolute best combination would be a locker in the rear combined with a set of dedicated snow tires on all fours, and I dont mean tires marked M+S, anything with a block tread can get that, I mean REAL snow tires like a set of Nokian Hakka Lts, preferably studded ( even unstudded the tires have things embedded in the rubber compound to aid in gripping, but when it comes to ice, you just cant beat studs ) . You want something that is going to transmit that traction to the road otherwise you can end up doing a pirouette. Ive got a couple of Volvos that have Dana 30 rears with auto lockers from the factory in them ( gotta love those Swedes, they REALLY know how to rig for snow and ice I've been running those Nokians on the things for years in winters ( their tires are made in Finland, they hold the world speed record for ice their friggen test track is a frozen lake in Finnish Lapland up above teh arctic circile
You put that combination on and it just feels like driving on a loose dirt road, and we rarely get much snow around here but we get ice storms that bring the whole state to its knees and we have no problem cruising around ( although during the last storm when the few cars on the interstate were crawling along at a walking speed in the right lane and I breezed by the cop with the radar gun parked by the ramp at 70 mph, he had a look on his face that was priceless You could tell he thought for sure I'd be going in the ditch, when in fact, it's just another day with that setup, just have to slow down around other cars and 4x4s to watch out for where they are sliding off to , let them go in the ditch call 911 and then be on your way

then come summer time swap to a set of summer tires and you will be all set. This will come as a shocker to a lot of folks, but you will be able to go more places with 2x4 and a locker and good tires than you will with 4x4 and open diffs no matter what the tires
It freaks out my wife's employees on snow days when I come to pick them up for work ( she doesnt want them out crashing their cars to get to work so she sends me out to round them up ) they know I own this huge truck and are expecting it to show up and instead I roll up in a little rear wheel drive car, but their apprehension goes away after we drive circles around all the stranded 4x4s all over town stuck on every hill that I waltz over with ease ( one fella with a new Range Rover looked like he was ready to burn his to the ground

Mind you , this is with the right tires, without them, your tail end will hit the ice with both rears spinning and will swing around your nose end in a dizzying little dance that your brakes will do nothing for... until you get traction and you launch into a tree , so choose wisely