91 GM with snow tires or find a 4WD vehicle?

[jaywish]

You may even consider checking crownvic.net for a part out.

If you go to disks make sure to grab the ebrake cables when you get a housing.

[Stealthlead]

For some reason all I see on Crownvic.net under 'for sale/wanted' are the two boards 'buyer feedback' and 'sponsor specials'. No personal ads. Its kinda weird over there :s

[jaywish]

Are you a member or a guest?

[Stealthlead]

Member, for a few years.

[pantera77]

Member, for a few years.

you need 25 or more post to see it

[Stealthlead]

Looks like its back to Ebay..

[Stealthlead]

Alright so I was talking with a co worker and he said he knows a guy who rebuilds rear ends. He made a good point and said if I'm going 3.73 and want it rebuilt, to do it with the current assembly/housing. He said trak locs are ok but to go with a posi (my housing is 8.8 I think?). He ended up getting me a quote for $1200 to remove the diff, posi 3.73 unit, rebuild the whole thing (new seals but use same axels) and reinstall it. He said he could do it in a day pretty much, maybe two. I don't usually like having work done this extensively in a shop and prefer doing it on my own but I know close to nothing about diffs and don't want to chance this. He's certified etc so it will also be warrantied. Then for the disc brakes in the back I can just do the conversion still on my stock rear end housing if I understand correctly. Would like to know if that's a fair deal and anything else I should have done while its dropped/I'm down there. I have a CVPI rear sway bar I have laying around and I'd like to do something about the rear sagging.

[jaywish]

They will probably not drop the rear for this job, just remove the wheels, and the differential cover.

The terms Posi & Limited slip are often used interchangeably.

Ask where he is getting the posi carrier and gears. Also if you need axles after it is opened, I suggest USA made not Dorman which are china made.

[Stealthlead]

The more and more searching I do the more I realize $1200 seems like a complete total rip off unless I'm missing something here...

[1987cp]

The Powertrax No-Slip units are under $500 and are supposed to be easy to install at home. IIRC, it just installs in place of the spider gears, even in an open-diff carrier ... and considering how easy it is to get to the C clips to remove the axles on an open-diff car, that's pretty easy compared to having to swap carriers.

Here's the video I was referring to ... had me definitely wanting one in the event I kept daily-driving a Panther in the wintertime. In theory, for snow-service needs, I imagine this should be better (lots better!) than a stock style Trak-Lok.

[Stealthlead]

Very fascinating... so let me see if I understand this correctly; they replace the spider gears making swapping easier but the gear ratio that's desired (3.73) is changed by replacing the pinion and ring gear. So what I would do if I was going to go with this unit is get the unit and a 3.73 pinion/ring gear correct? I'm doing this for advantage in the snow for now but I'm also planning on putting in a stroker motor down the line. While searching I found this thread - http://www.chevelles.com/forums/showthread.php?t=19311 and they say the lock right is better to handle HP but it says its a equal to a solid spool axle so I assume its not as good in the snow? Also, if they are that easy to put in, I might as well do that, the ring/pinion gear and seals myself and just rebuild the rear end right?

[jaywish]

A locking rear is a more ill mannered on turns as there is no slip between the right and left wheels. (The inner tire will spin or hop) The posi/limited slip allows some slip when cornering. Thus the car does not slide out as easily. With a 4x4 that has a locking hub feature you can turn that on and off. (on for high traction needs, off for regular driving) If you just install a permanently locking rear corner handling always suffers.

You would have to decide on the main purpose for the car.

The spider gears are a component of the differential carrier. Which can be "open" or "posi".
You could rebuild the rear but it is not a beginner project. It requires some tools e.g. a 1/4" torque wrench, regular torque wrench, dial gauge with mount, a socket big enough for the pinion nut, bearing/seal tools would be nice, a puller to remove the wheel bearings, a service manual would be helpful. Also you need a press though you can take the part to a shop. I would allow some few days for the car to be laid up. An experienced friend would be helpful.

Buying a JY housing has several advantages if you have a place to keep it while you prepare it. The car is not off line till you are ready to swap, you will likely replace the control arm bushings when you put in the rear. Also a great time to do the disk swap right on the new housing. It would still be good to have an experienced friend for the finer parts of the rebuild and the actual swap.

[Stealthlead]

Thanks for the reply! I now understand why a spool locker would be a very bad for a street application. I'm definitely going to go with some kind of limited slip. If those Power trax could handle a bit more power like I'm planning on down the road they would be a good option. That paired with 3.73 gears. I've never taken apart a rear end, but I'd be willing to try, I can be patient when I need to. If you guys think its a bad idea I will take it to a shop. But I'm willing to take time and I've got a buddy who can help me out. Although if I did take it to a shop I can then seeing the whole project being around $1k for the rear end, gears, limit slip unit etc. Also the more and more I think about it the more it makes sense to get a donor rear end because I can get it with the disc brake components, have it sanded/dipped/painted or whatever, totally cleaned out and good to just swap out. That way I'm not in a rush either. Also, I'm assuming the 92-97 rear end I get would be from a non-abs CV/GM correct, or does it not matter?

[jaywish]

it does not matter. Don't forget the cables.

[jaywish]

it does not matter ABS or not. Don't forget the brake cables. The late axles and housings are slightly longer which is perfectly fine. Just know what year you get. I can't remember the latest year housing you can use easily, maybe 97?

New ford 29 spline carriers are hard to find. If the axles need replacing you may be able to use 31 spline axles (got to research the length with manufacturer), then it is easy to get a new 31 spline carrier. Otherwise you need to find used. Perhaps you can find a housing with a posi in it.

There are threads here on rebuilding rears. The rebuild process is pretty much the same for solid rear mustangs also.