Detroit Lockers

[bsprowl]

I've got three 31 spline Detroit Lockers.  They may not be strong enoug as splines on the axles in the Maverick are slightly twisted. 

Can the axle side gears be changed to 35 spline or do I have to buy a different locker? 

[GerryP]

35 Spline uses a 3.25" case.  The 31 spline used a 2.89" or 3.05" (I forget the size but think it's 3.05 but for sure it's less than 3.25).

[Gregwill16]

3.06”

[bsprowl]

Will the 3.25 case fit in a Ford 9 inch carrier? What would I need to use the larger case in a 9 inch housing?

[Gregwill16]

Yes it will fit Bob. The 3.25” is the size of the side carrier bearings.

[Tommy-T]

If it's a drag race only car you want a spool anyway.
If it's a drive 10 miles maybe car you still want a spool.
If it's on slicks all of the time, even still you want a spool.

If you're going to drive on Drag Week or Power Tour, go with the Detroit.

I personally like street driving with a spool better than a Detroit Locker. A spool is completely predictable in all driving conditions.
2 Things I hate about spools...you cannot push a car with a spool. Once you turn the steering wheel even just a little, the car just stops and it takes 3 guys to get it to move. Secondly, in a parking lot the rear tires will screech loudly when you pull into and out of a parking space.

All of this said, my Jeep and my Comet both have 9" rears with Ebay NASCAR Detroit Lockers. They are cranky to drive and very loud around corners. Both get driven pretty long distances. They are embarrassing pulling into gas stations and such and I have had a few folks ask me what's wrong with my vehicle.

My track diff with 4.88 gears has a spool.

[bsprowl]

It' s a track only car.  I like a spool for the track but I'll be eighty in two months and  cannot push a car with a spool.

I'm fugal (my son says "cheap") so I don't like spending money but since the 33.0-12.0 tires twisted the splines and I want to run them (or 32-14 tires) I believe I should step up and change the axles and locker.  I'm building a carrier with new gears so this is the time to do it.

Thank allof you for the feedback.

[cjshaker]

2 Things I hate about spools...you cannot push a car with a spool. Once you turn the steering wheel even just a little, the car just stops and it takes 3 guys to get it to move. Secondly, in a parking lot the rear tires will screech loudly when you pull into and out of a parking space.

All of this said, my Jeep and my Comet both have 9" rears with Ebay NASCAR Detroit Lockers. They are cranky to drive and very loud around corners. Both get driven pretty long distances. They are embarrassing pulling into gas stations and such and I have had a few folks ask me what's wrong with my vehicle.

My track diff with 4.88 gears has a spool.

Tommy, just curious, what axle spline count do you run with your spools on the street? I don't have experience with spools, but always wondered how a 31 spline would handle the twisting with big tires. It's just a guess, but I think I would want 35 or bigger with that scenario. I wouldn't even attempt a 28 spline, even an aftermarket. I've wondered if my Strange 31 splines could hold up under a spool on the street.

Also, I've run several Detroit lockers, and none of them behaved like you've described. I've certainly heard the horror stories like you relate, just never experienced it. Are they old lockers? They have changed over the years.

[frankenfords]

My experience with lockers is that they like to coast a little bit, off the throttle, before making a turn, especially with a manual transmission. Coasting a little allows them to disengage fully so you don’t get the chatter that tries to shake the car/truck apart when trying to turn. I kind of like the soft ratcheting noise when making a tight part or off throttle turn. Lockers are cranky and take a little getting used to, especially with a manual transmission and in the rain, but once you learn the nuances, I love that when you jump on it it tries to go straight. I’ve used them in several daily driver type cars and trucks that got flogged regularly

[Tommy-T]

2 Things I hate about spools...you cannot push a car with a spool. Once you turn the steering wheel even just a little, the car just stops and it takes 3 guys to get it to move. Secondly, in a parking lot the rear tires will screech loudly when you pull into and out of a parking space.

All of this said, my Jeep and my Comet both have 9" rears with Ebay NASCAR Detroit Lockers. They are cranky to drive and very loud around corners. Both get driven pretty long distances. They are embarrassing pulling into gas stations and such and I have had a few folks ask me what's wrong with my vehicle.

My track diff with 4.88 gears has a spool.

Tommy, just curious, what axle spline count do you run with your spools on the street? I don't have experience with spools, but always wondered how a 31 spline would handle the twisting with big tires. It's just a guess, but I think I would want 35 or bigger with that scenario. I wouldn't even attempt a 28 spline, even an aftermarket. I've wondered if my Strange 31 splines could hold up under a spool on the street.

Also, I've run several Detroit lockers, and none of them behaved like you've described. I've certainly heard the horror stories like you relate, just never experienced it. Are they old lockers? They have changed over the years.

I run the NASCAR takeout Detroit Lockers that are very inexpensive on Ebay. They're tough but cranky.
I've run a spool against Moser and Currie 31 spline axles with no trouble. I'm talking about cars that drive less than a thousand miles annually.

[HarleyJack17]

I am thinking the Nascar variant is a tad different than a traditional Detroit Locker. At least from what I am seeing on the google. That may, or may not, explain the reasoning for different actions. Detroit Lockers have been known far and wide for strength as long as they are fully locked. Neither is to be confused with a "lunch box" locker. I am running one of those in a Dana 60 rear, and to date it has done fine. That is far from drag strip abuse though.

For the OP, if you still have questions, maybe call their tech line. As pricey as they are I would make certain before investing. 

[bsprowl]

My axles and housing are Currie 31 spline.  I didn't expect to find the splines twisted where they meet the unsplined part of the axle.  But the car had a big block chey (AA/Fuel Altered) running on alcohol so it wasn't a total surprise. 

[hbstang]

whats your power level that you are running? for more than 700hp you need to upgrade to 35 spline and run that spool on the track.you could run the helical gear posi from strange,the Strac.or detroit tru trac.much better than any detroit style locker.

[bsprowl]

Blair Patrick is projecting 800 plus HP in the low to mid 7000 RPM range.

I'm having a problem finding a carrier for 31 spline axles.  I have three Detroit Lockers but they are all for 31 spline axles. 

I found this at Speedway motors:  https://www.speedwaymotors.com/Speedway-Helical-Gear-Style-Differential-Ford-9-Inch-35-Spline,490855.html

I just called them and they think it will, of course.  And they couldn't tell me who makes it (several suppliers so it varies). Total cost with cut to length axles about $1150.

The other option is a Strange case with 3.25 carrier bearings, an Eaton Trutrac differential with Speedway axles total about $1700.

I'd use a 4.71 Zoom gear set I've had for years. 

[oldiron.fe]

        do not (cheap out on a track build) use a spool and axels a little stronger than you may need-- if break/loose traction with power or speed on one wheel you WILL go for unwanted ride !!!!                     lockers do better on street/ road/or circle tracks-      p.s. i run my 67 fairlane in the 10s car can go high 9s -i am in my 80s- no do not need a suupid ride on broken axel !!!!