2005 Rear Axle design

[T-BirdTom]

Is the rear axle on the 2005 T-Bird a clutched Limited Slip design or is it an open differential controlled by the traction control unit?

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[T-BirdTom]

So far I've found nothing that indicates the 11 Gen T-Birds had "Limited Slip" differentials. The exploded diagrams show no internal clutches for such a diff.
I'd been concerned the diagrams were generic Ford and didn't represent the T-Bird, but further reading suggests our birds fly with just one wheel pushing.
There are some nice pieces to add, however. Most are friction clutch types but there's also an Eaton/Detroit TruTrack that's available. I have one in my '33 street rod and I love it. I also used Quaiffe and Torsen pieces in my road race cars in the past. I much prefer the geared design of these over the friction clutch designs.
Here's what Ebay shows: https://www.ebay.com/itm/1150059059...pid=5338236430&customid=&toolid=10001&mkevt=1

I'm going to consider adding one.


Best wishes,
Tom

 

[biddle]

I am honestly surprised someone has this part as an offering. They also offer a "Grip N Loc Differential"

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[Liquidlounge]

I think some of the Lincoln LS guys were adapting 8.8 limited slips to the their 8.0's. IIRC, it wasn't super complicated.

 

[T-BirdTom]

Thanks Biddle,
I've had good luck with the TruTrack unit in my street rod. I have about 18K miles on it since 2009 and it's performed very well both on the street and on the road course (Road America) over the years. The units act like a speed reducer gearbox. All power comes in the same way but the left and right sides can vary in rotation speed through the gearing. There's an approximate ratio that will allow the inside wheel to lift and spin slightly faster than the outside wheel, but the outside wheel is still getting ~60% to 70% of the driving force. An open diff under similar conditions would just let the inside wheel spin and not drive the outside wheel. So, you can power out of the corners better with the TruTrack.
It's far happier on wet or slippery pavement than a Locker type diff or a welded unit. Also, it's silent compared to Locker types. Being geared, one doesn't have the friction heat of the clutches inside a traditional "limited slip" differential.
Best wishes,
Tom

PS: since my diff is stock, I added 3 ounces of Molybdenum Disulfide oil (Mr. Moly brand) to the differential. This was done as a preventative effort to help the bearings, seals and ring/pinion gears. The ratio suggested is between 5% and 10% of the capacity of the item in question. In the 2005 T-Bird the Diff holds between 2.5 and 2.7 pints of gear oil. I figured 2 ounces of the Moly would be roughly 5%. There was room for two ounces, so I then tried to add more. I got one more ounce in before it started to drool a bit. I took it out for a drive with speeds up to ~75mph and all's well. If there was a tiny bit of gear noise before (my 75 year old ears don't notice such things much!) it is all gone now.

Mr Moly Lubrication | Engine and Transmission Gear Oil Supplement | Copaslip Anti-seize | LBCarCo | Little British Car Co

Note: The Fill/Drain Plug on the 2005 Bird has a ceramic magnet crimped into it on the "oil" side. It had a small amount of sludge stuck to it. The material was so fine that I'd need a microscope to see anything. Using some brake cleaner I diluted the sludge down in a glass container and couldn't see any individual particles. That's good news. Years ago when I was racing vintage sports cars, we always attached a ceramic magnet to the oil plugs of engines, transmissions and differentials. At oil change times it was always nice to do a quick health check with the magnets.
Best wishes,
Tom

 

[biddle]

I think some of the Lincoln LS guys were adapting 8.8 limited slips to the their 8.0's. IIRC, it wasn't super complicated.

Ah, this explains it. Ford didn't really make many Thunderbirds, as compared to other mass produced vehicles, so as a result very few wanted to make aftermarket custom parts for them. Borla was probably one of the few big names that manufactured an exhaust.

 

[T-BirdTom]

While I had my 2005 on the lift, I noticed these spots that look like there had been some type of bracket.
Anyone able to help out with what's supposed to be there?