Rear end problem

[LanceB]

Changed gears in 77 from 2.73 to 3.55. It runs much better, however, I have started to notice a sound when I am idling though. It only does it when I am rolling off from a stop, in stop/go traffic, etc. and not giving it much gas. Once I give it gas I am fine. It is kind of a catching sound from a lack of a better way to describe it. I got hosed by the guy that put them in, he was supposed to put in new A/C also, and that doesn't work right either among other things. It is not worth pursuing anything from him, I just want to get it fixed right and never mess with this guy again. I suppose I need to find someone reputable to tear into the rear end again and find out what he did wrong. I know he said he couldn't get (Dyno?) gears to fit in this rear end right and he ended up putting GM in it. Any advice is appreciated.

 

[Chas]

a sound in the rearend when your idlning and not moving?
i just had a new rearend installed...went from 3:08 to 3:55...they changed the speedo gearing to calibrate that as well...you need to find a reputable tranny shop...that knows this car...its so diffrent from everyday cars...i learned the hardway. i have a guy that does my cars and trucks repairs...i took him the vette and he totaly blew the diagnosis...it ended up costing me $400 extra in repairs...after he changed the U-joints he told me i was good to go..i trusted him...then i get the clunk again. im not gonna go back, so i find a guy thru a friend here with a vette...told me this place knows the car better than most. the core was shot, so i had to by the whole diffrential...plus eat the core to repair...the ring bolts had backed out and wasted the interior of the housing..i do have more sound from the car now than before...at 70mph im doing 3500 rpm and before i was doing 2400 rpm...so its ready to jump when i tap the throttle..i love this new rearend.

so it really matters to find the right shop for your ride...take you time and make the calls...please let us know how you do.

Changed gears in 77 from 2.73 to 3.55. It runs much better, however, I have started to notice a sound when I am idling though. It only does it when I am rolling off from a stop, in stop/go traffic, etc. and not giving it much gas. Once I give it gas I am fine. It is kind of a catching sound from a lack of a better way to describe it. I got hosed by the guy that put them in, he was supposed to put in new A/C also, and that doesn't work right either among other things. It is not worth pursuing anything from him, I just want to get it fixed right and never mess with this guy again. I suppose I need to find someone reputable to tear into the rear end again and find out what he did wrong. I know he said he couldn't get (Dyno?) gears to fit in this rear end right and he ended up putting GM in it. Any advice is appreciated.

 

[GTR1999]

Well if you're getting a noise while idling then it's not in your differential.Now if you're getting a noise while let off the gas then that another story. Before the gear change I'm guessing you didn't have any problems? I noticed your signature states 81 but you said this is for a 77? The noise doesn't matter but the two car use different differentials. Were the gears new or used? You can get gears for a 63-79 vette from a couple of suppliers,Richmond, US Gear,Yukon,etc some are better then others but they all should be quit if set up correctly. Without seeing it, I goign to guess the pattern is off,meaning either the backlash or pinion depth wasn't set right. try to determine if your noise is indeed while moving or not to help pin point it.


Chas,
Unfortunately mid to late 70's had the problem you had- ring gear bolts backing out and wrecking the differential. Good thing is you can still get parts and rebuild them to hold up well.

 

[Chas]

i bought a rebuilt one and threw the entire old one in the scrap heap....you are not the first to tell me about the bolts...i just wish the first guy had opened it up and told me so i could rebuild mine..we live and learn!...it is much better now...Thanx,
Chas

Well if you're getting a noise while idling then it's not in your differential.Now if you're getting a noise while let off the gas then that another story. Before the gear change I'm guessing you didn't have any problems? I noticed your signature states 81 but you said this is for a 77? The noise doesn't matter but the two car use different differentials. Were the gears new or used? You can get gears for a 63-79 vette from a couple of suppliers,Richmond, US Gear,Yukon,etc some are better then others but they all should be quit if set up correctly. Without seeing it, I goign to guess the pattern is off,meaning either the backlash or pinion depth wasn't set right. try to determine if your noise is indeed while moving or not to help pin point it.


Chas,
Unfortunately mid to late 70's had the problem you had- ring gear bolts backing out and wrecking the differential. Good thing is you can still get parts and rebuild them to hold up well.

 

[LanceB]

I have an 81, but this is my brothers 77 (which I help him with). Really there is more to the story...I met a guy at a car show that said he knew a lot about corvette rear ends. My 81 was making crazy sounds and he fixed it for about half the price of a local shop here and it ran great. I was pretty stoked. My brother was interested in lower gears in his 77 and so we trusted this guy to do it. The story gets a little psychotic from here. He does this on the side, and he actually introduced me to the body shop that is painting my 81. A couple of weeks go by and he keeps making excuses why it isn't done yet. He did mention the pattern was off, so he had to order different gears. Well one day the body shop guy calls and said he recommends me and my brother going to this guys house and get the 77, tow it whatever. He says that the guy working on it is a pathological liar and he wants to earn my business so he didn't want to see me get screwed over. He told me he saw this guy driving around in it. It was a weird call. I half expected the car to be in Mexico or something. Anyway I go to his house that night and he isn't there. The 77 is in the driveway with a cover over it. After seeing it I feel a little more comfortable, I decided to come back for it in morning. He calls me that day and said he will have it brought to my house that day all fixed. I come home and it is in my driveway. The odometer is stopped, the front end is hit (with a shoddy spray paint job over it to try and hide it), and this new noise I descibed when the car is stopping and going is happening. The AC doesn't work also (something else we paid him to fix). So I guess the only good thing is that it is in one piece. We just put it in the garage and trying to find someone trustworthy to take it to.

 

[GTR1999]

Sounds like you have had your share of experiences with that vette. It is always better to do the work yourself,if you can. I don't know what level your mechanical abilities are but the more you can do the better off you're going to be. These cars always need attention, if you have to pay a shop every time you'll be spending enough to buy a C6!

Sorry to hear of the problems you had with someone you trusted. Is there any recourse you can take? Since you said he had a problem with the gear pattern and he's liar how do you know he installed new gears? At this point I would drop it out again and go through it to see axactly what you have. Too bad you weren't in my area, I would help you.

 

[LanceB]

I have tried to work on them myself about a year 1/2 ago. The biggest jobs I have done myself are installing new brakes and rotors, and disassembing and reassembling the steering column to fix a broken turn signal. I was very successful at this, (although horn doesn't work now after putting all of that steering column back together). Work has been very stressful and long hours, as well as a recent marriage have kind of kept me from trying to do work myself. I can tell the gears were put in because 77 accelerates rapidly now. I have jackstands, so I can definitely get to the rear end, but I am afraid once I take it out it will probably stay that way for awhile. I am a little afraid I am going to screw something up (end up costing more in the long haul), but I couldn't make it any worse than now. Is it that difficult to take the rear end out and redo it? I don't know what "pattern being off" really means so that is why I am a little hesitant to do it. I guess it is one of those things I need to just jump into and see what happens.

 

[Ol Blue]

LanceB
Sorry to hear about your bad experience on the differential. If you do have the ability/time to remove your differential, you might consider having it rebuilt or exchanged by Ikerd's Corvettes in Bedford Indiana, ony a couple of hours from you. He is probably one of the best around and has been supplying Mid-America for years.
http://www.ikerds.com/

Ol Blue from Bloomington IN

 

[GTR1999]

I have jackstands, so I can definitely get to the rear end, but I am afraid once I take it out it will probably stay that way for awhile. I am a little afraid I am going to screw something up (end up costing more in the long haul), but I couldn't make it any worse than now. Is it that difficult to take the rear end out and redo it? I don't know what "pattern being off" really means so that is why I am a little hesitant to do it. I guess it is one of those things I need to just jump into and see what happens.

Well it sounds like you have the right attitude,that's the first step. Removing it can be a job if it's rusted. You will save a lot of money while learning how your car is put together. Rebuilding it would require some more experience.You'll need some very good measuring tools and experience measuring to .001" It's not completely out of the question but if you have to buy tools and don't have a clean area to work then it's not worth it.

Ikerds, Bair's or Van Steel... they're all capable to rebuild your differential so shop around. Usual cost for a standard rebuild starts about $500 plus shipping. Just because he used a different gear doesn't mean they're new,he could have bought a set off ebay or these corvette forums on the net. Of course he might just have screwed up the setup and wrecked the gears,problem is you just don't know.

If you want to go over things send me a PM and I'll be happy to help you out.