Rear Axle Questions

[Takakjian]

I'm hoping to do some upgrades to my rear axle for my W250 (Dana 70). Truck is mostly on the road, occasionally in the snow or on the beach. I need some adviceand have some questions:

1) Disk Brakes, found a good source for the parts from https://www.circletracksupply.com/e...dge-trucks-1988-1993-dana-70-srw.html?cat=495 Any experience or things I should be cautious of, or definitely do ? Will I have to change anything up front in the brake
system ?

2) 3:54 Gear ratio, standard rear end. Looking to upgrade to a Posi or locker (hate not going anywhere in snow). Not sure what is best or the real difference between them. What is best ?

3) Is there a later year or generation rear end I should look to get (maybe with disk's already as OEM) and build that rear up ? Would a later year axle housing even fit my 93 ?

Any advice would be greatly appreciated. Thanks, Kyle Takakjian

 

[Bob4x4]

I would not want a full time locker to drive in snow and ice.A selectable locker is great. you would have the best of both.You will have to do some mods to the braking system to adjust the pressure front to rear as well as coming up with a park brake option

 

[RWherley]

I have a factory limited slip in my 93 W350, and its nice but is real tight and you must use extreme caution in snow or it will put you sideways

 

[BigPapa]

Nice truck.

I have a tight factory LS in my '98 RWD and it's worthless on snow and ice and sometimes even taking off or accelerating on a wet street. May be different in a 4X4.

I just aquired a '92 D350 that the PO put the EGR rear disc kit on. I haven't had any experience with it nor have I towed with it. Here's a quote from him on a problem he had:

We went on to Alaska and got into brake problems with the EGR kit. A local brake place replaced the rotors and pads, and the RR caliper. Getting the correct clearance of pad-to-rotor was the problem since old Cadillac parts are hard to find; finally they took "too-thick" pads and sanded them down to the correct clearance. This has happened a few times since and caused a few long conversations and custom work to get them working properly.

 

[DVolk]

Maybe a air locker , id keep the factory drum brakes , but on rear end questions call Randys Ring & Pinion

 

[Takakjian]

Guys thanks - any options, information is helpful

 

[Bob4x4]

https://www.ringpinion.com/b2c/Part...odelID=480&Side=Rear&DriveType=4WD&DiffID=288

 

[RWherley]

I cant speak for SRW trucks but my duelly is also prone to massive under steer on slick roads with the limited slip the entry speed or power going into turns is to much

 

[Bob4x4]

With an open diff the side without being driven acts as a rudder to keep the truck in line-when both tires have power the rudder effect is gone

 

[wolfsmurf]

I'm hoping to do some upgrades to my rear axle for my W250 (Dana 70). Truck is mostly on the road, occasionally in the snow or on the beach. I need some adviceand have some questions:

1) Disk Brakes, found a good source for the parts from https://www.circletracksupply.com/e...dge-trucks-1988-1993-dana-70-srw.html?cat=495 Any experience or things I should be cautious of, or definitely do ? Will I have to change anything up front in the brake
system ?

2) 3:54 Gear ratio, standard rear end. Looking to upgrade to a Posi or locker (hate not going anywhere in snow). Not sure what is best or the real difference between them. What is best ?

3) Is there a later year or generation rear end I should look to get (maybe with disk's already as OEM) and build that rear up ? Would a later year axle housing even fit my 93 ?

Any advice would be greatly appreciated. Thanks, Kyle Takakjian


View attachment 97820

i found several kits for the dana70 to convert to disk but i was talked out of it by several peeps due to the parking brake not holding worth a crap with those kits. you will also possibly have to change the proportioning valve to an adjustable one since the factory is for drum rears and set up differently. apparently you can buy the brackets for k20 chevys and it bolts right up and then just go buy the correct calipers for said truck.

 

[EDankievitch]

Just wanted to chime in Really Nice truck! I'd be had perssed to change out the Axles on it. I had well over 500,000 miles on my 89 when I sold it. Rear breaks were a pain but I always got them to work. I liked the disk set up that my 02 had only the front pads were half the size of the 89's and would last less than half the miles. The newer american axle seems to have the best breaks and emergancy break but it comes with other headaches can you say factory ball joints. I'd just rebuild everything you have and enjoy it.....

 

[AnonEd]

I have same truck with 4.10:1...and an exhaust brake. Dynatrac might have a disc conversion, but at 80 mph top end and not a quick trip to it I've only needed more braking power once, and the fifth-wheel, 8-10% dirt road and 100-degree weather made that unusual. I'd expect a circa-2003 disc'd Dana 70 (or 80 hybrid) would be the least complex complete axle swap.
OE limited-slip was manageable in the snow but it seems to vary based on which is looser...the limited-slip or friction coefficient of tires on it. Detroits at both ends now and in rare snow-use lock only the right hub for some directional control--there's a reason most factory rear lockers often don't work in high-range, the understeer point made by RWherley (though a SRW shouldn't be as bad). Frugal me would say keep what you're got in good shape, get an ARB or E-Lcoker if you must, buy a decent air compressor and just air down on the beach.

 

[BigPapa]

2003 and up have AA axles. I think the D70/80's with disc rear were available '01-'02.

 

[AnonEd]

Scott's memory is better than mine. Can't speak to their longevity but in dually stopping tests from 60 the Ram came up shorter than F&C, and shorter than an Acura CL Type S, BMW 3 and a Ford Lightning.

 

[Takakjian]

Thanks for all the tips everyone, holding tight right now just continuing to think it through...