Diff ratios

stephen low · #1 (**permalink**) 05-24-2021, 03:50 PM

Hey guys

Looking at an upgrade to my noisy jag diff.

It is a 3.54 ration LSD and am told you can't get new replacement crown and pinion for this ration but you can if it is a 3.07 ratio.

So what are you all running in your cars and what is suggested?

I've only a 5L and 15" 295 wheels.

Cheers and thanks

Steve

Tom Wells · #2 (**permalink**) 05-24-2021, 05:39 PM

Stephen,

It looks as if Richmond Gear is still making them in the 3.54 ratio - and lots of other ratios, and Summit Racing (among others) are selling them for under $200US.

Look here: https://www.richmondgear.com/auto-pa...ing-and-pinion

It wouldn't be a surprise if you found a Richmond Gear outlet down under...

The ring and pinion may fit OK as is, or it may need Dana 44 ring gear bolts which are a little different from the Jag - it's been too long for me to recall, but Richmond could likely clear that up for you.

I think you can probably find some rebuild parts for the PowerLok too (DuckDuckGo is your friend).

Hope this helps,

Tom

jknich · #3 (**permalink**) 05-24-2021, 07:15 PM

Jeep 3.31 or 3.54 Dana 44.

kyleb · #4 (**permalink**) 05-25-2021, 03:26 PM

G’day Slowy.
Got mine from Denis Welch Motorsport in 3.54 and mated it with an Auburn gear 19 spline LSD centre. Basically makes it a Dana 44. Vic Spiteri put it all together for me and it runs smooth as silk.. Not cheap, but I feel I’ll save in the long run!
As you know I’m putting around 600hp through it.

https://www.bighealey.co.uk/jaguar/axle-5?page=2
https://www.summitracing.com/parts/aub-542085
V&A Spiteri Jaguar - Independant Jaguar Specialists

incoming · #5 (**permalink**) 05-25-2021, 07:44 PM

The transmission. cam and a lot of other factors come in. I have an FIA car with a "slightly modified" 351w, wide ratio Toploader and 3.54 Salisbury rear. I can easily mistakedly start off in third gear and am constantly looking for fifth.
Honestly, I did 135ish once in my car. Secondaries opened for a minute.

joyridin' · #6 (**permalink**) 05-26-2021, 04:11 AM

It would be easier to buy a new LSD differential and upgrade the gears to Dana 44 instead of using the outrageously priced Salisbury gears. Do you know if it is a 19 spline or a 30 spline? I switched to a Richmond Power Trax, and used Dana 44 gears. It was a pretty easy switch from the old Salisbury unit. The Jag set-up uses a collapsible sleeve on the pinion whereas with the Dana gears, you have to shims.

jknich · #7 (**permalink**) 05-26-2021, 08:42 AM

Also the Dana 44 pinion uses a different spline pinion yoke.

https://dazecars.com/dazed/Diff.htm

stephen low · #8 (**permalink**) 05-26-2021, 04:17 PM

Guys

I am constrained by what diff will fit the solid mounts on the car and more particularly by existing drive shaft / hub set up.

This was changed only a few years ago to allow me to use an outboard braking system from a later model Jag over the earlier XJ6 in-board brake set up. As well to properly fit new Vintage rims under my guards.

Perhaps should have done this then but its too late now, so am stuck using the diff housing I have.

Kyleb, I like your idea, though note replacement new crown and pinion will cost me about $1100 AUD on current exchange rates with the UK.

Still my goal is to silence the diff to best capacity and this may need to be the way.

Andy at Spitteri has asked if I can appear with the car and do a drive so he can hear my issues.

Planning that with the soft top on so he gets maximum exposure to my noise issues.

Send me a PM with your email mate so we can some further discussion off-line please.

Steve