So I would like to convert my open 9'' diff to Trac Loc but not sure what all I would need for the conversion. Do I only need the carrier or is there more to a swap. I know there are other options like lockers and spools but I do mostly highway driving, just would like to have a little more grip on hunting and fishing trails than an open diff only being 2WD. Any help you can provide will be greatly appreciated. Thanks. -DJ

 

I think you're looking in the right direction then. So many people seem to think that they automatically need a Detroit Locker to go to the store!
Anyway, you're correct that you only need the carrier. In a 9" you can just bolt your old gears on and go (relatively speaking that is) where on the Dana axles you need to be sure to get the correct carrier for your gear ratio.
One thing you need to know for sure beforehand though, is whether you currently have the lighter duty 28-spline axles, or the heavier-duty (and later just standard I think) 31-spline axles. The diffs are almost all available in both, whereas some (such as ARB) no longer make 28 spline versions of their differentials.

Ford did use two or three main carrier bearing sizes over the years, but that is only for the case/chunk/3rd member/center section/hogshead/thingy and I'm pretty sure does not matter to the diff carrier since the inside of the bearings are all the same. Only the outsides changed.
Really not sure what vehicles got what bearing, or if you just have to take it out and measure, but it would be good to verify since the bearings are one of those "well, while I'm in this far..." kinds of things.

Others will know more I'm sure, and can confirm or deny some of what I said. Good luck. I did the same for my Bronco a long time ago. Don't even notice it until you need it (which was the whole point) compared to my other Bronco's Detroit.

Paul

 

1Ton is right on it. Plan on new axle shafts. My 1979 was 28 spline, so I had to buy 31 spline axles when I swapped in a TrueTrac. Even if they make 28 spline diff's, you should upgrade to stronger 31's. Like 1Ton said, you'll need to know which bearing size you have. You also need to know which retainer plate you have. The plates are specific to bearing size, and some have 3/8" bolt holes, some have 1/2" bolt holes. Do yourself a favor and get the heavier plates that slip on. The only way to know which parts you need, is to disassemble the rear end. That way you know which bearings, seals, and plates to get. And you can measure your axle shaft lengths.

The easiest route, is to order a complete center section from a reputable source. I got mine from Speedway and it was perfect. It also came with a new nodular case.

 

It's a great point. It does not cost any more or less for the differential with 31 splines vs 28. Only the axle shafts themselves add to the price, but since many come with the new bearings already installed, some of this additional cost is mitigated somewhat.
But in the overall scheme of things, the shafts are not that expensive to begin with. So it's a plus-plus in my book. The book I helped write by the way, since I went over and over this when I did my first limited-slip, and as much as I wanted to go with 31-spline upgrade axles, I decided I had to save the $200 bucks and stick with my old ones.
Figured it was a reasonable decision to save some money given the financial strains I always put on myself. But given that I did not get around to installing the diff for over six months, I could have just gone with the new axles and absorbed the darn extra cost! Oh well, live and experience. Not necessarily "learn" from it of course, but at least get to experience it.

 

This is all correct and good advice.

I see no reason to upgrade to 31 spline for highway use as 28 spline (if currently equipped) will be just fine.

You will need to first pull an axle and count splines before ordering your trac-loc differential.

In order to get case preload and backlash measurements you will need some machinist tools.

 

Since you have an open differential, the easiest thing to would a lunchbox locker.

 

Thank you all for the help, definitely going to do the research before I tear it all apart and have both sets (28 or 32) ready to order as soon as I determine which I have. I saw the mention of speedways carrier, does anyone else have any recommendations? Looking for the option that will not break the bank but I don't want to put in junk either. Thanks again for all the information so far.

 

I have ran the detroit Truetrac in the front of a 79 F150 and loved it. If it were my truck I would spend more money initially and get a Truetrac, simply because you won't be needing to rebuild a clutch pack like you would with the Trac lok. While the clutch packs don't need rebuilt every 3000 miles, Murphy's law will cause the Trac lok clutches to be worn when you need the Trac Lok most. I would agree that I don't think that you will need a full locker, but I think that you will be happier in the long run if you choose a geared LSD.

 

Have you used one on the street? Do they have the same quirks as a Detroit locker? I wouldn't mind having a bit more traction for my f-150, don't need maximum beef as I'm just daily driving the truck and pulling a camper every once and a while.

Jess

 

Yes I use them on the street every day, they work the same way a Detroit locker does.

 

I have ran mini spools, lunchbox lockers, Detroit lockers and Trac loks and I can tell you in my experience the only street friendly Units are the Detroit’s and trac loks.

The detroits behaved in no way shape or form the same as the lunchbox. Detroit is far superior.

i just removed my d60 spartan lunchbox after 4K miles because I couldn’t stand it any longer and installed a trac lok.

 

I have a Detroit in the rear of my F250 and lunchbox lockers in my other 2 vehicles. They operate the same way, the only difference is the Detroit locker is quieter since it is the soft locker version, but I can't really hear my lunchbox lockers either unless I roll the window down and stick my head out during a slow turn.

 

I recently rebuilt my Dana 60 and put the power Lock in. It must have been longer than I remember for a Limited slip. I've been running the modern electric lockers for too long. It's hard to get used to these older clunker/clanger locks. Mine is finally started to quiet down, but I jump every time in pings.

 

A Power Lock shouldn't be clunking or clanging at all, its a clutch type limited slip.

 

As 00t said, it should be silent and smooth. The actual Dana Power-Loc (or however they speeled it) is considered one of the more aggressively tensioned of the clutch type limited-slips. But it's still quiet.
My first inclination for noise would be to say you need more friction modifier. If you did not add any to begin with, that would explain a lot. And from what I've seen, the manufacturer of the oil saying "compatible with limited-slip diffs" does not mean it's got the correct amount of additive.
In fact, I don't personally know anyone who's used that type of gear lube that did not have to add at least one container of friction modifier. I had to add two to quiet down my Ford Racing Traction Lock (or whatever it's called?) in my 9 inch.

Quieting down may be the fluids finally soaking into the clutch plates. But it might also be mechanical since your noise is not the usual grinding/groaning/grumbling/grunching sound typical of clutches slipping.
Because yours sounds like the mechanicals making noise, are you certain the differential is properly rebuilt? Tolerances set perfectly?
Is this is a new differential unit, or did you just rebuild the existing stuff?

Did you do anything else while you were in there? Maybe it's a u-joint on it's way out, or something unrelated.

Good luck. Noise is not usually a good sign, but it's not usually the end of the world with diffs either.

Paul