Rear End lets go after only 300,000 miles !

[Jack P.]

Time to rebuild Rear End ! I only got 300,000 miles out of it......!

Hi, took my son for little ride in car to feel thump in rear or drive train. Let him drive down driveway, he goosed the gas , bad idea ...

Something let go in drive train. Stopped car, no drive shafts hanging, but...

Car will only go forward or backward one revolution of wheel then stops. It will do it in all 4 gears forward and reverse.

Called flatbed, to get car back to my garage.

It seems that the rear let go....

I get the car up on jack stands.... time for rear end removal/ strut rods bushing, body mounts, tranny removal, and if possible crossmember , later after rear removal..plus a lot of stuff that is showing wear after 60,000 miles in the last three years.

I will ask for help after the weekend , just to make sure I take it apart in the right order....

It will be a real job to do on jack stands....I may offer some Lobsters for lunch as a reward for coming up to Maine to get the tranny off my chest or to help pry the crossmember off the frame...

Pictures later.....Son leaving Sunday, for new job in Seattle at Amazon as a robotics engineer...

Thanks in advance for you kindness and understanding , and supporting me as I cry under the car.......should be quite interesting...

Jack

[Gary R.]

Re: Rear End lets go after only 300,000 miles !

Hi Jack
300k on a 66 with a 1st design posi is pretty good. Those were noted for cracking and once the crack reaches the cross shaft hole it will bind up and break. You might have sheared a tooth as well. Call me and I can go over any questions on removing it and what to check inside- although I think once you remove the cover it will be no mystery.

[Ed S.]

Re: Rear End lets go after only 300,000 miles !

Jack - good luck, hope all goes well with the repair. FYI - I will be pulling my differential out of my 64 soon - have a nasty sound coming from it. Had never pulled one from a C2 before so I did some research by searching "how to remove a differential from a C2 corvette". Found a very interesting YouTube video that you might find helpful. It is in 2 parts, total run time is about 16 minutes. It provides step by step procedures to remove the rear end - along with a few very important "cautions". Here is the link to the video:
https://www.youtube.com/watch?v=Q3HXnIFdkj8.

The video is produced by a guy named Gary Vosberg, he is the owner of a business called VTech Corvette LLC - website is VTechCorvette.com. The video is also on the company website. For what it is worth - I am not endorsing or recommending VTech Corvette - just found the video useful. Good luck again - hope your repaired diff lasts another 300k miles.

[Jack P.]

Re: Rear End lets go after only 300,000 miles !

Jack - good luck, hope all goes well with the repair. FYI - I will be pulling my differential out of my 64 soon - have a nasty sound coming from it. Had never pulled one from a C2 before so I did some research by searching "how to remove a differential from a C2 corvette". Found a very interesting YouTube video that you might find helpful. It is in 2 parts, total run time is about 16 minutes. It provides step by step procedures to remove the rear end - along with a few very important "cautions". Here is the link to the video:
https://www.youtube.com/watch?v=Q3HXnIFdkj8.

The video is produced by a guy named Gary Vosberg, he is the owner of a business called VTech Corvette LLC - website is VTechCorvette.com. The video is also on the company website. For what it is worth - I am not endorsing or recommending VTech Corvette - just found the video useful. Good luck again - hope your repaired diff lasts another 300k miles.

Hi Ed,

Thanks for the link. I will keep all undated as I start work on the car this week. I have taken most of the car apart as I restored it for my 48 state trip in 2010. The rear is a 3.70 from a 68 Corvette that I put in in 1971. It has never been worked on except for fluids since then.

My cross member has never been out, and the sombreros are shot and the strut rod bushings are almost gone. I hope all comes out without too much cursing .

Jack

[Jack P.]

Re: Rear End lets go after only 300,000 miles !

Hi Gary,

Should be fun getting all the bolts out without breaking any of them. I start on it this week. It is a 3.70 from a 68 Corvette that I put in the car in 1971. Sounds like something is stuck as the wheels will only make about 1 rev before they lock up both forward and reverse.

I will keep all updated as I take things apart.

Jack

[Paul D.]

Re: Rear End lets go after only 300,000 miles !

Jack, not wanting to cheat anyone out of a lobster lunch, but why are you pulling the tranny? as Gary said, I bet the story will be told when you open the pumpkin! If you suspect something in the tranny, I would remove the drive shaft first and then see which direction remains bound up...the rear or the trans. I'm betting on the rear. Chip.

[Jack P.]

Re: Rear End lets go after only 300,000 miles !

Hi, my tranny plug is rounded off and my muffler pipes are welded at mid section, can't get a wrench on plug. Tranny is good, but throw out bearing has been squealing , clutch has 60,000 miles on it, and I am not getting younger. Once I start taking the rear apart, I may as well set up the car for the next 60,000 miles. # 2, 3 & 4 body mounts gone (48 years old) ...bushings shot on strut rods,

I drive all year round so the under body gets salt in winter....

The problem will be the rear carrier, no way those bolts are coming out of it.....I will take the rear off and leave carrier one cross member at first....I may then drop cross member and replace sombreros ......

I will post pictures every day...unless I can't breath with the tranny on my chest....lol...

Lots of good video on U Tube for removing rear, plus I have taken most of the car apart in the past, just avoided the rear and it was working fine until this year....

Jack

[Ed S.]

Re: Rear End lets go after only 300,000 miles !

Jack
Where are you going to have your diff rebuilt, or... are you going to exchange it for a rebuilt one? I am in the same sit as you - my diff is making noise and I need to take it out and send it off for an overhaul. I prefer to keep my original diff as opposed to swapping it for a rebuilt one. Do you or anyone have a recommendation for a reputable diff overhaul business?

[Jack P.]

Re: Rear End lets go after only 300,000 miles !

Hi Ed,

There is only one fellow I would send it to. Gary Ramadei (14833) . He rebuilt my original steering box two years ago , just before my Corvette Vagabond European Tour 2012. (There is a post on this forum). Many members have used him and all will tell you the same thing.

I sent it to him, and he did a unbelievable job, replacing needed parts, and most importantly, adjusting it properly. The car drove great, even with the primitive 66 power steering unit. Last month , before all this rear end stuff, I had replaced the power steering valve ( 45,000) miles on it in 3 years. I noticed some play in the wheel.

I gave Gary a call before I touched it. ( you can adjust the box). He got right back to me the same morning and told me what to do . I followed his directions and the box was like new. I will post some pictures later ( new computer ) . I will keep all posted on my progress.

Jack

[Timothy B.]

Re: Rear End lets go after only 300,000 miles !

Jack,

FWIW, consider removing the complete rear and crossmember as one unit. The only issue is the bolts holding crossmember to frame then a LARGE pry bar to seperate bushing. The weight of the rear will assist in this removal but you don't want it to fall on the floor when it releases.

Also, remember safety first, do you have some heat out there?

[Kenn S.]

Re: Rear End lets go after only 300,000 miles !

Liberal doses of Liquid Wrench penetrating oil will help nuts/bolts a lot. The stuff is magic and odorless (unlike PB Blaster...wife complains mightily when I pull that stuff out). Soak all nuts/bolts, let sit, soak again, sit, and then wrench them off. You can't get to the body bolt caged nuts, and hopefully you won't have to cut them off (spinning caged nut...must pull body at that point, although it sounds like you're heading that way anyway).

It won't necessarily help with the bushing, but you'll break fewer bolts, maybe even none. If you can save them, Richard Fortier will clean and re-plate them. If they look bad, he'll replace them with new for you.

Bair's is also a great resource. They did my steering box...unbelievable job. I took my diff unit to a local shop, which has done a nice job as well (and I could keep an eye on it...). But, in my area restoring cars is a passion (Auburn, Indiana), so it's not hard to find a good shop for that sort of thing. Maine, dunno... But it sounds like you have a direction to go.

[Terry M.]

Re: Rear End lets go after only 300,000 miles !

Time to rebuild Rear End ! I only got 300,000 miles out of it......!

Hi, took my son for little ride in car to feel thump in rear or drive train. Let him drive down driveway, he goosed the gas , bad idea ...

Something let go in drive train. Stopped car, no drive shafts hanging, but...

Car will only go forward or backward one revolution of wheel then stops. It will do it in all 4 gears forward and reverse.

Called flatbed, to get car back to my garage.

It seems that the rear let go....

I get the car up on jack stands.... time for rear end removal/ strut rods bushing, body mounts, tranny removal, and if possible crossmember , later after rear removal..plus a lot of stuff that is showing wear after 60,000 miles in the last three years.

I will ask for help after the weekend , just to make sure I take it apart in the right order....

It will be a real job to do on jack stands....I may offer some Lobsters for lunch as a reward for coming up to Maine to get the tranny off my chest or to help pry the crossmember off the frame...

Pictures later.....Son leaving Sunday, for new job in Seattle at Amazon as a robotics engineer...

Thanks in advance for you kindness and understanding , and supporting me as I cry under the car.......should be quite interesting...

Jack

Jack
Not to be too pickey, but further on down thid thread you say this differential is from a 1968

So inquiring minds want to know:
Do you know how many miles were on the 1968 differential and then added to the miles you put on it there are 300K miles on it

or

Does your Corvette now have 300K on it?

Either way it is a remarkable number of miles that few of us will reach with our Corvettes, but some of us will exceed that number with other vehicles and the durability of the hypoid differential is of interest to us.

[Jack P.]

Re: Rear End lets go after only 300,000 miles !

Hi just got back online , forum sign on problems. I put about 250, 000 on the 68 rear , from 1971 to present. I will assume the rear had at least 50,000 miles on it, I took it out of a wreck (yellow) ? Corvette myself in the days when you could go into a junk yard wth a wrench and lunch

[Donald O.]

Re: Rear End lets go after only 300,000 miles !

Hi just got back online , forum sign on problems. I put about 250, 000 on the 68 rear , from 1971 to present. I will assume the rear had at least 50,000 miles on it, I took it out of a wreck (yellow) ? Corvette myself in the days when you could go into a junk yard wth a wrench and lunch

It only lasted 300k miles????

What a POS!!!

Can't they build anything that lasts?

[Jack P.]

Re: Rear End lets go after only 300,000 miles !

So it begins...Day 1

I started today working on the car. Turned on heater in garage, keeps it about 50* if outside is below 32* and warmer if above.

First goal was to jack up car to view damage if possible

Next remove mufflers
Next to remove half shafts

Time 3 hours . One problem was not being able to rotate wheels more than 1 / 4 turn. That made unbolting haft shafts difficult because of small turns of wrench at odd angles on u-joint nuts.

There is little doubt that my rear end is dead.....

Now what to do next. Carrier bolts from cross member will never come out. It will be very difficult to unbolt the rear from carrier as there is no room to get at top bolts.

My sombreros are shot (48 years old) the only way I will get the rear out of the car is to take off the cross member with the rear end.

All the components (Strut rods bushing shot) , springs, drive shaft, have to be take off to drop the rear.

I am on my back doing this. Any suggestion on my next days work will be welcome. I am soaking all in penetrating oil .

Here some pictures of today's work

Parts on the floor, good 2 days work (7 hours slow me ) without any broken bolts !




Support of spring / TA , jack is holding up shock mount not rotor