Rear end grenaded? 3.23 to 3.73 questions also
04-27-2009, 11:57 AM
#1
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Rear end grenaded? 3.23 to 3.73 questions also Well, i bought the car in my sig 2 weeks ago and as i was coming home the rear end started to clunk when i went around turns. The entire car shakes and clunks so something is obviously way wrong. Brought it to the shop today and the guy told me he heard a mustang like that a few years ago with an auburn posi and it was as simple as putting synthetic gear oil in it? Doesn't sound to me like anything as simple as that but what do i know. I went ahead and ordered 3.73's from summit as well as an install kit for it so i'm hoping the ring/pinion gear is skipping teeth or something? I know it's hard to diagnose without hearing it but i'm really curious what happened, got to reading about 10 bolts and from what everyone on here says, they're garbage. When i get this fixed to i have to worry about breaking something every time i hit it hard off the start? I bought this for a fun summer cruiser...
With the 3.23's to 3.73's how far off is my speedo going to be? And do i just get a mail order tune for the car to solve that problem?
Here is the email from the guy i purchased the car from.
am really sorry to hear about the rear end. I really have no idea what would have happened. I drove the car to work and back (I work in Van Wert which is 35 miles one way) for about 2 or 3 weeks ,then up to school (in Flint, MI, 180 miles one way) one time and back, and any driving in between there. I know it was put together right because I checked the backlash and everything and all was within spec. I replaced the carrier cross pin, cross pin retainer bolt, the axle c-clips, and put in a shim from speed inc. that re-shims the stock posi units. The spider gears were all in spec and were 100% acceptable to reinstall. I put at least 1,500-2,000 miles on that rebuild and I never had an issue. The only reason that I even touched it was because the axles had too much end play due to posi wear and that is what the speed inc. shim was supposed to fix. I worked for an ACDelco dealership as a mechanic so I have did a few of these in my time there so I know everything was right.
Just wanted to see what you guys think... thanks!
With the 3.23's to 3.73's how far off is my speedo going to be? And do i just get a mail order tune for the car to solve that problem?
Here is the email from the guy i purchased the car from.
am really sorry to hear about the rear end. I really have no idea what would have happened. I drove the car to work and back (I work in Van Wert which is 35 miles one way) for about 2 or 3 weeks ,then up to school (in Flint, MI, 180 miles one way) one time and back, and any driving in between there. I know it was put together right because I checked the backlash and everything and all was within spec. I replaced the carrier cross pin, cross pin retainer bolt, the axle c-clips, and put in a shim from speed inc. that re-shims the stock posi units. The spider gears were all in spec and were 100% acceptable to reinstall. I put at least 1,500-2,000 miles on that rebuild and I never had an issue. The only reason that I even touched it was because the axles had too much end play due to posi wear and that is what the speed inc. shim was supposed to fix. I worked for an ACDelco dealership as a mechanic so I have did a few of these in my time there so I know everything was right.
Just wanted to see what you guys think... thanks!
04-27-2009, 01:39 PM
#2
This link can show you how your RPMs will change when swapping gears:
http://www.race-cars.net/calculators...alculator.html
A mail order (or local) tune can get your speedo corrected.
http://www.race-cars.net/calculators...alculator.html
A mail order (or local) tune can get your speedo corrected.
04-28-2009, 09:48 AM
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How much would a mail order tune run me? I have heard people either have really good luck with them or the car runs like death... I have a spare ECM for the car that i can send out, is there any DIY things i can do to correct my speedo? My buddy wants me to dyno tune it when he goes to do his cutlass.
04-28-2009, 12:13 PM
#5
If you are going to get it dyno tuned, I would just wait for that.
With HP Tuners it is a real easy thing to do. I wouldnt pay to have it programmed for the new gears if you are planning on getting it dyno tuned in the near future. I'm not sure if any of the handheld programmers can do it.
With HP Tuners it is a real easy thing to do. I wouldnt pay to have it programmed for the new gears if you are planning on getting it dyno tuned in the near future. I'm not sure if any of the handheld programmers can do it.
