How much power would you run through a spider-type 9 inch

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SadbutTrue said:
A stock type traction lock, as it came from Ford 9 inch... how much power would you stick through those before going to a spool/Trutrac/other more modern posi design?

That's all going to depend on the build of the axle. If you're talking about an axle that came out of a truck, it'll take quite a bit more torque than one that came out of a car. The truck axle assemblies had heavier walled axle tubes, 31 spline axle shafts, and basically the same trac-loc and r&p as the car.

Wanna keep it all together? 35 spline, or the new super 40 spline setup (full custom, requires D60 outers, IIRC) Run a quality locker, or a FULL SPOOL, mini spools break. Alloy shafts from a quality manufacturer, Moser, Superior, Yukon, etc. Step up to 1350 U-joints, or even 1410, which is what is used on 1 ton trucks, you'll have to replace your yokes at this time too. A quality driveshaft will make a difference in performance, and you'll need to upgrade that as well :spot: :spot: :spot: :doh: :doh: :doh: :OT: :OT:
(sorry, wife intervention) to facilitate the new heavier duty joints and yokes.

To answer your question, the factory trac-loc is pretty much crap. Mine operates as a fully open unit, and has for years, I'm not even sure when I killed it, but the wheels turn so I run it for the time being (new axle in the bed of the truck, just need parts for front axle before I swap it in :D )
 
any comment on the above post hearne? i definitely don't want to be running "crap." There are so many choices as far as lockers, spools, and the like go...what would be the best fora 400 hp/450 lb ft street 351w, meant to be driven daily and hopefully without it breaking often??
 
I like the factory trac-loks, they operate smooth and quiet. If drag racing is all you do, a detroit locker is the way to go, but for street performance with the occasional trip to the drag races, it should be more than adequate. If the unit is in good condition and has 31 splines, you shouldn't have any problems. Even if it does go out, new clutches are only about $50 I think.
 
SadbutTrue said:
any comment on the above post hearne? i definitely don't want to be running "crap." There are so many choices as far as lockers, spools, and the like go...what would be the best fora 400 hp/450 lb ft street 351w, meant to be driven daily and hopefully without it breaking often??
Yea, first of all the factory traction loc isn't "crap" . They do however wear out. But they can be rebuilt, not a hard job to do.And second of all not all pickups came with 31 spline axles. Some did, some didn't. I have had both a 70 and a 77 F100 that both had 28 spline axles. I'm now running a trac-loc in my 89 V8 Ranger with a 4 speed Toploader and it was pulled from a wrecked 94 or so Explorer, mileage unknown. It's been under the Ranger now for a year and still works fine. It's held up to a 400 hp 5.0 so far. And with big 275/60/15 tires. I have no doubts about running a trac-loc with your combo. If you can afford a different unit, then go for it, but I don't think you need it :nice:
 
D.Hearne said:
Yea, first of all the factory traction loc isn't "crap" . They do however wear out. But they can be rebuilt, not a hard job to do.And second of all not all pickups came with 31 spline axles. Some did, some didn't. I have had both a 70 and a 77 F100 that both had 28 spline axles. I'm now running a trac-loc in my 89 V8 Ranger with a 4 speed Toploader and it was pulled from a wrecked 94 or so Explorer, mileage unknown. It's been under the Ranger now for a year and still works fine. It's held up to a 400 hp 5.0 so far. And with big 275/60/15 tires. I have no doubts about running a trac-loc with your combo. If you can afford a different unit, then go for it, but I don't think you need it :nice:

You're right, the F100, and even the EB came with the 28 spline units. The F150, F250, E150, E250 (many of the 250 units came with the Dana 60, 61 or 70 axle, some were shipped with the 9" however) and they all came with the 31 spline unit. 35 spline were never a factory option that I am aware of, simply an aftermarket conversion.

I'm not a fan of the trac-loc, it fails more often than not, and for the money, I'd rather have an aftermarket offering that is far superior in strength. Not to mention that the trac-loc just won't offer the traction that a quality differential like a Detroit will bring.

If you're short of funds, the trac-loc is fine, be warned that it isn't nearly as strong as it could have been.
 
Well, I figure if the factory type held out for decades on engines like the Boss 351, Boss 429, etc... it should be enough for my car even if I upgraded to decent 235 rear tires and an engin ewith the characteristics I just noted. I'll definitely look for a locker, but won't hesitate on a stock type.
 
Gummi Bear said:
You're right, the F100, and even the EB came with the 28 spline units. The F150, F250, E150, E250 (many of the 250 units came with the Dana 60, 61 or 70 axle, some were shipped with the 9" however) and they all came with the 31 spline unit.

I'm not a fan of the trac-loc, it fails more often than not,
I've also seen many F150's with 28 spline axles. As for failing more often than not, I'll have to disagree, the three I've had, none have failed. And I'd like to see that E or F250 that had a 9 inch.