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  1. favorite gear oil for the IRS setup?

    Factory Five Roadsters
    I ordered my rear IRS from Mike Forte https://cobradreams.com/2019/12/11/ordered-the-irs-center-and-knuckles-today/ and it had to be drained since it wasn't on a pallet... I know many of you have installed the IRS, and I don't want to start a holy war - but I've seen tons of info on Amsoil...
  2. Paint or Not To Paint - Transmission & Diff

    Factory Five Roadsters
    I'm considering painting (or at the very least polishing and coating with Sharkhide) my T56 transmission/bellhousing and IRS Diff housing. I know there are a few that have done this. I'm looking for your experience and guidance: What paint/process did you use? Was it worth the effort? How...
  3. For Sale: 2004 Mustang Cobra SVT IRS 8.8 Complete 31 spline Rear End 38k miles

    Parts For Sale / Wanted
    Sold SOLD 2004 Mustang Cobra SVT IRS 8.8 Complete 31 spline Rear End 38k miles I decided to change directions with my IRS and no longer need this. Here are the details: Donor was a 2004 Mustang Cobra SVT w/ 38k miles Purchased from Midway Mustang in Davenport, IA on 3/17/2014...
  4. How to remove Rear Diff Cover

    Factory Five Roadsters
    Hello all, I recently purchased a beautiful FFR Mk3 and am in the process of changing out all the fluids. Last night I did the trans and rear differential. I'm stuck on the rear diff and need some help though. The car has an Independent Rear Suspension with 1997 Thunderbird Super Coupe rear...
  5. Differential question - Torsen vs Trac-Lok

    Factory Five Roadsters
    I am in the planning/starting to acquire parts phase and I am wondering if I should go with a Torsen or Trac-Lok? I'm sure this has been asked before, but every answer will be different depending on their application. MY application will be a variety of track, street and possibly the...
  6. IRS Pumpkin/Differential Installation

    FFR Type 65 Coupe
    I know this is an old topic, since I read as many posts as I can find on both forums. (I do like Cobra99's suggestion - real nice!) But - my differential looks different from others, and so I decided to post a fresh look at this. My standard width IRS differential did not fit into the cage as...
  7. 4-lug/5-lug, Drum/Disk

    Factory Five '33 Hot Rod Forum by E/T Wheels
    I just scored a 1995 3.27 axle for $100. No leaks, no cracks, no noises, no looseness but no brakes. If I put the Fox length axles in it, what calipers do I get? Are they any different from the SN95 calipers? Are the backing plates and mounting plates the same? I'm looking at pulling it...
  8. Differential Gear Oil

    Factory Five Roadsters
    I have the 8.8 rear with the truetrac differential, and am about to fill the diff. with gear oil. I wasn't able to find anything specific about this, and I'm not sure if it makes any difference;but; when filling the differential with gear oil, I have seen the process described on the forum...
  9. Want to Buy: ALUM Diff Housing for IRS

    Parts For Sale / Wanted
    I would like to buy an aluminum differential housing for 8.8 IRS. Prefer without gears and differential but will consider with.
  10. For Sale: jaguar xjs irs complete

    Parts For Sale / Wanted
    i have 2 complete 1985 jaguar irs rear ends. both are complete with calipers an 4 coil overs. both were pulled out of running cars and are solid. $650 each OBO jeff 928-458-0003