Doing a conversion to a manual tranny and would appreciate some advice regarding diffs.
Wanting to change to a 3.54 ratio, I bought a diff from a more recent model, 3.54 with speed sensor on the back cover - just what the doctor ordered.
Ooops, there lies the problem, it's for an outboard brake car and I want to stay with inboard brakes.
The diff casting is different and there is nowhere to attach the calipers !
Q1: If I was to shop for another diff, was there ever a model which had the speedo sensor on the back plate AND had inboard brakes?
I saw on youtube a video of an (inboard brakes) XKE diff which had machined adapters bolted to the diff for the attachment of the calipers.
Q2: Does anyone know if these adapters can be bolted to my 3.54 (I think it was a 94, 6cyl)? - if yes, can they be sourced in scrap. (New for XKEs they sell for $375 !!!!!)
Please feel free to add any other relevant comments/opinions

 

Leolete,

XJSs changed to diff sensors from the late 80s. And right up until April 1993, they had inboard brakes.

So any XJS made in that period will potentially suit you.

Cheers

Paul

 

Many thanks for that news - much appreciated
Will keep it in my back pocket as right now I have 2 diffs neither of which will work "as is".
I will have to trade/sell one or both of them to buy a "third".
I'm waiting to see if anyone can answer the second question.
Cheers.

 

I'm confused. Are you sure the diff came from an XJS? Because on an outboard brake XJS, the parking brake cable retainers/abutments that go to the outboard parking brakes mount to brackets in the exact same location as inboard calipers. When I first converted to outboard calipers and a manual gearbox on my '87, I retained my old Dana diff for a short time until I found a late 3:56 Salisbury. The cable brackets mounted to the inboard brake mounts on the Dana, and when I swapped in the Salisbury, the brackets bolted up in the exact same way. I could have mounted inboard calipers there just fine. Are you sure someone didn't leave the cable brackets bolted on to your diff?
A picture would help.

Jon

 

This is great info, thanks.
As soon as I saw the cable brackets I realised the diff it was for an outboard brake car.
I did a GVI as we say in the aero field, and it did not look correct.
It didn't occur to me to remove the brackets and compare castings.
Will check in a couple of days and update the thread for future users.

 

Caliper mounts are on the output shaft bearing housings, so worse case, just swap output shaft assemblies.

 

Firstly thanks for the advice.
Unfortunately, not in my case. On my 1986 HE, the rear calipers mount directly to the main diff casing, the output shaft housings are different and have fewer attachment bolts.
The problem is solved, however, as the calipers will attach to where the handbrake "ears" were bolted on the 3.54 that I bought, which is where I think you are correct.
The caliper attach bolt heads will now be near the diff casing (lots of fun to install) and not outboard of the caliper.

 

Firstly thanks for the advice - it has proved a lifesaver.
The problem is solved. As you said the calipers will attach to where the handbrake "ears" were bolted on the 3.54.
The caliper attach bolt heads will now be near the diff casing (lots of fun to install) and not outboard of the caliper.
(On my 1986 HE, the rear calipers mount directly to the main diff casing, the output shaft housings are different and have fewer attachment bolts).

 

An '86 would have had a Dana diff, so yes, the calipers bolt on from the opposite direction than the Salisbury. You also need different inboard discs, as access holes in them are in different locations. The discs are otherwise the same.

Jon

 

Do I need the access holes?
I did a trial fit, attaching the calipers with the bolts going in from the diff to outboard as the threads are in the (I think) output shaft housing.

 

One other thing. Make sure the output flange bolts on the Salisbury are long enough before you mount it in the cage. Outboard caliper diffs used shorter flange bolts since they didn't have discs to pass through. I don't know if the stock bolts will be long enough. The output flange bolts from the Dana MIGHT fit the Salisbury flanges, but I don't know for sure. You can remove the bolts without removing the flanges if you clock them to exactly the right position. Use a brass drift to knock them out. It's a lot easier to do with the diff out of the cage.

Jon

 

Not sure. To use a Dana diff, you need the access holes in the right location to reach the caliper bolts with the disc in place. Not sure if the reverse is true.

Jon

 

So Jon, am I correct in thinking I do not need the disc holes for any reason?
With regard to the output shaft flange bolts, are you referring to the bolts where the driveshaft is attached?
If yes, surely their length will depend on the thickness of the driveshaft u/j.
I want to make sure I'm not misunderstanding anything.

 

You have several things to consider, the thickness of the disc, the camber shims, and the thickness of the half shaft flange. The bolt has to pass thru all of them and still have sufficient length to accept the nut.

I don't know if the need the access holes for anything with the Salisbury diff. I went to outboard discs when I changed from a Dana to a Salisbury, so I never had to deal with inboard discs on the Salisbury. Hopefully, someone else can answer.

 

Since I have both my original and the 3.54 replacement diffs on the floor in the garage I'll just compare the bolt lengths.
Have a good one.

 

The mystery deepens
Thanks to the advice from the Forum I think I'm ready to freeze the design, BUT now we come to the rotors.
I'd like to change mine but when trying to order I see "Dana" and "non Dana" versions.
I used my old ones (1986 Dana) for the trial fit and all looked correct, so why the difference.
Looking at internet photos of the two it seems the difference is in the position of the holes for caliper bolt access.
But for the Salisbury, the calipers are bolted from the diff casing side so holes are not needed.
Does anyone know the exact differences between the two rotors?
Final curiosity question - why do my old rear rotors have machined grooves around the periphery? (BTW I have one solid and one grooved!)

 

As far as I know, only Dana has the access holes, but I think dimensions are same. Original equipment rotors have a silencer ring around the periphery.

 

Hey maybe I can actually answer a question for once instead of always asking!

I just installed a 3.54 diff into my 83. 100% compatible. The 95/96 diff output flanges and input flanges are the same.

The 95/96 diff does have two metal brackets used for the outboard brakes. They are mounted where the calipers would go on an inboard system. Take off those brackets and bolt your calipers up. Nothing to it. I haven't wired my speedo sensor yet (and coincidentally just posted a new thread about that, which is how I saw yours!) so I can't help with that.

Same thing for the e-brake stuff - the two arms holding on to the cable are mounted to the calipers, not the diff, and since you can use normal inboard calipers as previously stated, the e-brake stuff doesn't change.

 

Great to have confirmation of my "trial fit" of the parts - it does give confidence for going forward - thanks.
Next step will be to wait for other replies regarding the difference, if any, between the Dana / non-Dana rotors.

 

Thanks, that makes sense but I'll wait for further replies to change your "I think . . . ." to "I know".
Don't want to buy the wrong parts - rotors are heavy things to return !