Could anyone tell me the rear end ratio on a 1996 Grand Marquis LS? My differential is on the way out (I was told one of the splines was broken off when it was last serviced, and have been babying the throttle since until I get a chance to replace it). I have a friend with a good condition 8.8 trac lok 3.73 rear (out of a accidented '96 mustang) that he will give me no charge, and was curious if a) it'll fit (IE, will the axle splines from the LS match up), and b) how far off is this from the stock ratio. I believe the stock ratio for the LS series for this year is 3.27:1, but can someone confirm that? I know the GS series is a 2.73:1, i'm just not sure if the LS is a 3.08:1 or 3.27:1 for this year.
If it -will- fit without any major modifications, can I just replace the speedometer gear to keep the speedo accurate within reason? (It's got the digital dash, but I'm assuming it still just takes a mechanical input from the transmission.) Any ideas which gear to buy?
There are a couple of reasons I'm considering this over just grabbing another LS differential from a wrecker.. The trac lok rear is free for the taking, and I know it's history; it's never been abused, and only had 40,000 miles on it before the 'stang it was in was broadsided at a light. I don't do any major miles on this car, so i'm not worried about the higher ratio affecting fuel economy. I fill up about once a month right now, if i have to fill up once every three weeks, that won't bother me much... I live up north, so the limited slip is pretty appealing for snowy weather in the hills, and the stock LS differential doesn't have it.. I'm guessing the higher ratio will "wake up" the car some too, which I wouldn't complain about..