hello ever one, this was brought up before by other people. i have a a4 automatic 04 gto. i get the winding noise from the rear end and the thunk in the trunk. car runs great nothing wrong but i said i better get it checked out or have them put on the cr insulators bolts for the thunk in the rear end and it should be fixed. i find out today i have a bad hub and bearings and my rear diff is also bad. it still runs and still wood. but they found it all out today. so ever one with those noises will have that problem i bet. they have to take all the rear end and axle and mufflar off to fix and to fix it all under warranty its over 5000$ so my gto is down for a week or two. just to get the parts they said a week or more. but i will post more as i find out more. thanks eric

Shouldn't they issue a recall to all owners for this? :blink:

Originally posted by 04GOATGERM@Apr 1 2005, 09:10 PM
Shouldn't they issue a recall to all owners for this? :blink:
One would hope so. :blink: :unsure:

they have some guys from gm claims coming to look at it so maybe they will if they have alot of the cars come in for the same prob.

Originally posted by ERIC_EROC@Apr 2 2005, 03:24 PM
they have some guys from gm claims coming to look at it so maybe they will if they have alot of the cars come in for the same prob.
well they looked at my gto and the rear end and its still bad, thet put a whole new rear end rear dif in and it still get's the whinning noise but just at high speeds now. so its still not right. so they did all kinds of test with lap tops and wires hooked up to my gto all day. what there doing since the stock rear dif keeps doing this with the gto, there building by hand a aftermarket better rear dif made by dana or something like that name they told me. so i will see after this 3rd time getting fix. i will lwt you all know.

I dropped my GTO off at the dealer to get a couple of things worked on end of last week. I had them look at the rear end because of the winding noise. I found out today that they have a rear end on order for my car and they should have it in and replaced by Thursday.

This can be typical of improper break-in, or just a bad ring gear/pinion setup. No accusations here, but consider:

During initial wear-in, although the ring and pinion have highly polished and "mated" surfaces from the factory, there is still a microscopic mis-match between two otherwise separate objects. If a car is run HARD before surfaces have run-in, the gears will not polish properly and will wear against each other, one surface tearing metal from the opposing surface. This is especially true with similar metals because the metal's crystalline structure is similar and they tend to "interlock" before they are polished sufficiently for lubricant to isolate them. In other words, high points aren't worn down and they interact.

Engine bearings are made of a different alloy metal than the crank which helps with differing crystal lattice structures and opposing surfaces don't find the right "matchup" to drag the surface. On a ring and pinion, unfortunately due to the tremendous loading and stress, only a very few metal alloy formulas can withstand the loads, so dissimilar metals are not an option.

One reason the owner's manual asks you to drive the car varying moderate speeds is that these parts are "wearing in" on both the front and back sides of the gears (accelerate and decelerate loading) and you want to minimize surface loads during that break in time. If you go out and run your car on the strip at 500 miles, you're taking a huge risk of rear end failure.

All rear ends will whine at certain speeds. They're designed that way because all the ring gear teeth are evenly spaced and anytime you rotate anything that makes noise as it rotates, it will have a certain harmonic frequency at which it is most noticible. (That's why, for example, tire makers have varying tread block sizes and spacing on their tires). Most cars will whine the most around 50 mph because that is a speed at which you seldom drive.

I don't mean to accuse anyone of mistreatment, but I've seen some posts that make my skin crawl. This is one fine automobile. Take care of 'em, guys! :(

Thanks for the info. I have around 7000 on the car now and have not taken it to any track. Due to the fact I want everything happy before I take that chance. I see what you are talking about. I will probubly have to give another 4-600 for break in on the new gears. B)

ok im the one who started this topic, as fastgoat said they were going to put in a new rear end, yes they did that for me and it still makes the winding noise, so they didnt want a rear end off the asmb line so they got the same rear end but hand built it and did it again. my gto still does it but only from 40-52 and above 80mph i have almost 7000 miles on mine. so now there rebuilding my gears and hand building a dana rear end for my gto for the 3rd time yes 3 times now. so i hope this isnt a issues again. im finding out this is a problem for alot of gto owners.

Originally posted by ERIC_EROC@May 13 2005, 05:39 PM
ok im the one who started this topic, as fastgoat said they were going to put in a new rear end, yes they did that for me and it still makes the winding noise, so they didnt want a rear end off the asmb line so they got the same rear end but hand built it and did it again. my gto still does it but only from 40-52 and above 80mph i have almost 7000 miles on mine. so now there rebuilding my gears and hand building a dana rear end for my gto for the 3rd time yes 3 times now. so i hope this isnt a issues again. im finding out this is a problem for alot of gto owners.
well i got my car back last week for over the 3rd time and after they put the aftermarket rear end its finally fine. no noise. no thunk in the trunk either. they fixed that. so its all good. need some breaking in. but all good.

Anyone know how much power the IRS is rated for?