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My all-time favorite is the 65 GTO, which the 67 Fairlane looks similar to.
When I was 19 and broke I bought a 66 Malibu for $1100.
People weren't willing to let go of their 65 GTO nearly that cheap, especially the convertible one that tortured me during junior high... sitting in a driveway across the street from the school, not being driven, but the guy wouldn't sell it. :mad:

After narrowly escaping a life-changing/ending experience in my 66, as we were taking all of the usable parts from it in preparation for the junkyard, one of the guys helping me said "Hey, there's a 67 for sale on the bulletin board" (this was at an Air Force auto hobby shop).
It was a 6-cylinder, so I was able to use my 283, TH350 that I had rebuilt just before the crash, and disc brakes I had just installed on the 66 into the 67.
I've been babysitting (and occasionally driving) it ever since November 1990, and over the past few years have done a complete new drivetrain, from 12-bolt to performance 4L60e, to Dart-based 383.
Unfortunately, the "Legion of Doom" is quickly subverting all my plans of nights of cruising and days at the track... but that's another story.

All the best with your project. Enjoy it, and be safe out there!
 

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Discussion Starter · #23 · (Edited)
Well, the day is gone and so are the old stock upper trailing arms! I worked on it for about 9 hours. I learned some important things. First the Hotchkis bushing removal/installation tool I bought from Summit was a must have. If you have to do this kind of work with the car on the ground you NEED that tool or one like it. Second, I need a lift! Third, I’m too old to spend 9 hours getting up and down and crawling around on a concrete floor. Forth, road dirt and rust and penetrating oil works wonders on your hair! Did I mention I need a lift?
The job went very well otherwise, I had no rusted, stuck bolts or anything like that. I sprayed the bolts with penetrating oil and wire brushed the rust off the exposed ends before removing them. I was able to then wrench them off without any problems. The bolts actually look pretty darn good after wiping them off. Not bad for 57 years old. The arms were pretty rusty and the stock bushings were a little beat up but not terrible. Removing the bushings took a while. Probably the longest time because everything was hard to get to. I had to sand on the washer that was part of the removal tool because it did not want enter the “ear” on the axle housing to fully push out the bushing. I beveled the outside edge of the washer on one side and put that side towards the bushing and then it found it’s way in with no problem.
Installing the new bushings went pretty well except for the break line connections on top of the differential were very close to blocking to installation tool. I had to use a bottle jack under the pinion (as suggested above) to raise and tilt the rear axle back to get the arm bolts to line up with the bushings. Everything else was just slow because it’s hard to work in tight spaces. The only thing I’m worried about is the rubber break line the comes off the body and connects to the “t” on top of the diff. I had to lower the axle WAY down to remove the rear springs and that rubber hose could stand to be longer. I hope I didn’t stress it because it’s the original Factory hose. I may end up replacing it. It should have been replaced when the car was restored but some people are not as safety conscious as I am I guess.
The pinion angle was visibly wrong before I started. The transmission shaft was pointing noticably downward.....and so was the rear pinion! I struggled to be able to measure the transmission angle because there was nothing to attach the angle guage to. I attached it to the universal joint at one end of the cross on the transmission side as it was perfectly on the bottom (just not sure if that surface is square with the shaft). It was 6 degrees sloping down towards the rear. The angle on the differential pinion was also hard to measure as well but I attached the angle gauge to the bottom of the pinion and fudged it to align with the flat surface there. It looked pretty square with the universal joint yoke on the pinion side. The angle there was about 2 degrees down sloping to the front. So both the trans and the rear pinion were pointing down. I could tell that just by looking.
The newly installed rear upper trailing arms are sloping down towards the rear by a degree or two. So when we get in the car and the body settles down over the axle a bit more the upper arms should be about level and that may raise the pinion a bit more. So I set the rear pinion angle to 4 degrees pointing up towards the front. If I understand correctly that should put it about perfect when we are in the car. Whatever it is it should be MUCH better than what it was before. I’ll drive it soon and see if there is any vibration during acceleration or deceleration and tinker if necessary.
Thanks for all the info. Even though I hurt all over I think I was lucky today. Been a long time since a job went smooth.
 

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Discussion Starter · #24 ·
I have been reading up on universal joints today. From what I have read universal joints can operate at as much as 30 degrees or more Of angle between their yokes. The key seems to be the rpm at which they are operated at. The more angle that is present the less rpm they can reliably handle. The charts I’m seeing show that the preferred angle for typical u-joints at 5000 rpm is 3.25 degrees. That’s driveshaft rpm. At 70 mph with my tires and rear diff gears my driveshaft will turn at 2733 rpm. At 3000 rpm the u-joints are supposed to handle 5.8 degrees of angle. So if I drive on the highway at 70 then I’ll be pushing the limits on U-joint angle. So yeah, my 6 degrees is pretty much at maximum tolerated angle. I will have to look at raising the rear of the transmission at some point to get to the standard 3 degrees.
 

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You have your vertical angle. But you also have the engine or pinion offset. This makes a compound angle. Generally you can measure from both sides if the frame(usually straight) and compare the drivers frame to the center of the pinion and passenger frame to the center of pinion to the drivers frame to the center of the transmission yoke and passenger frame to the center of the transmission yoke.

Usually the engine is offset towards the passenger side. The pinion is usually not as offset so there is almost a slight compound angle.

If you have a compound angle you almost always have the option to run a double cardan u joint. If you have a carrier bearing the bearing can be offset to lessen angles. But generally a double cardian joint will give you plenty of angle.

U joint size also affects angle. 1310 can run more angle then 1410 etc. Then you have solid non serviceable vs serviceable that have zerk fittings and hollow channels.

Generally I try to run solid U joints. You put it in reverse and hear a clunk your joints are shot. U joints are cheap and not that difficult to replace with the right tools. Try to run within your angles. But if you can drive 90mph without vibration then a a shortened lifespan on a part that cost less then $10 its not that bad.
Lots of things can cause vibration. Before you blame the u joint angles or driveshaft balance inspect your tires. A computerized alignment is recommended. But a tire wearing because of a bad rear bushing/bearing, or steering will show up in the tires and may cause a vibration.
 

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Discussion Starter · #26 ·
You have your vertical angle. But you also have the engine or pinion offset. This makes a compound angle. Generally you can measure from both sides if the frame(usually straight) and compare the drivers frame to the center of the pinion and passenger frame to the center of pinion to the drivers frame to the center of the transmission yoke and passenger frame to the center of the transmission yoke.

Usually the engine is offset towards the passenger side. The pinion is usually not as offset so there is almost a slight compound angle.

If you have a compound angle you almost always have the option to run a double cardan u joint. If you have a carrier bearing the bearing can be offset to lessen angles. But generally a double cardian joint will give you plenty of angle.

U joint size also affects angle. 1310 can run more angle then 1410 etc. Then you have solid non serviceable vs serviceable that have zerk fittings and hollow channels.

Generally I try to run solid U joints. You put it in reverse and hear a clunk your joints are shot. U joints are cheap and not that difficult to replace with the right tools. Try to run within your angles. But if you can drive 90mph without vibration then a a shortened lifespan on a part that cost less then $10 its not that bad.
Lots of things can cause vibration. Before you blame the u joint angles or driveshaft balance inspect your tires. A computerized alignment is recommended. But a tire wearing because of a bad rear bushing/bearing, or steering will show up in the tires and may cause a vibration.
Interesting, did not think about the angle in the horizontal plane. The vibration that we noticed before was only during acceleration so that’s why I started looking at the pinion angle. There was no vibration while decelerating or coasting even down a mountain in 3rd with engine braking at 65 mph. Everything on the car is new right now so looking mostly at assembly problems but I hear ya. If my changes don’t solve the problem I’ll be looking for other culprits like you mentioned.
Thanks for the tips.
 

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Discussion Starter · #28 · (Edited)
Well I still have a vibration problem. Gets pretty rough at 60 mph under medium to hard acceleration.
Here are the details before adjusting pinion angle:
67 chevelle resto mod
1. engine and trans are new. Driveshaft was shortened. Yokes are aligned.
2. front end suspension was rebuilt stock last year.
3. rear end is original except for new upper arms
4. transmission angle: negative 6 degrees.
5. pinion angle: negative 2 degrees with nobody in the car.

Here are the details after installing new adjustable rear upper arms:
1. Transmission angle: still negative 6 degrees.
2. driveshaft: level
3. pinion angle: now positive 4 degrees with nobody in the car
4. engine/trans side-to-side offset: not sure yet but not visibly noticeable
5. vibration seems to have moved up to a slightly higher speed.

Next steps:
First I’ll get some folks in the car to see if that changes the pinion angle and how much. If that does not change the angle then I think I’ll try adding 2 more degrees positive to the pinion to match the transmission. If that does not work then I’ll start putting my go-pro cam under the car and try to capture any movement of various parts.
Coasting at 60 is smooth as silk so I don’t think anything is out of balance. Seems to only be a problem when under torque at higher speed. I can open the secondaries and pull hard in 2nd gear up to maybe 50 till I need to back off and it is smooth as silk through that. But further acceleration in third to 55 or 60 mph and things get rough. Feels like the vibration is in the front somehow.
Could this be a bad pinion bearing or something else in the rear end?
The steering wheel bounces and the whole car shakes. Mainly noticeable in the front.
The car doesn’t pull to either side so the alignment seems ok. And again, coasting at 60 feels like a new car.
 

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Discussion Starter · #29 ·
Well I still have a vibration problem. Gets pretty rough at 60 mph under medium to hard acceleration.
Here are the details before adjusting pinion angle:
67 chevelle resto mod
1. engine and trans are new. Driveshaft was shortened. Yokes are aligned.
2. front end suspension was rebuilt stock last year.
3. rear end is original except for new upper arms
4. transmission angle: negative 6 degrees.
5. pinion angle: negative 4 degrees with nobody in the car.

Here are the details after installing new adjustable rear upper arms:
1. Transmission angle: still negative 6 degrees.
2. driveshaft: level
3. pinion angle: now positive 4 degrees with nobody in the car
4. engine/trans side-to-side offset: not sure yet but not visibly noticeable
5. vibration seems to have moved up to a slightly higher speed.

Next steps:
First I’ll get some folks in the car to see if that changes the pinion angle and how much. If that does not change the angle then I think I’ll try adding 2 more degrees positive to the pinion to match the transmission. If that does not work then I’ll start putting my go-pro cam under the car and try to capture any movement of various parts.
Coasting at 60 is smooth as silk so I don’t think anything is out of balance. Seems to only be a problem when under torque at higher speed. I can open the secondaries and pull hard in 2nd gear up to maybe 50 till I need to back off and it is smooth as silk through that. But further acceleration in third to 55 or 60 mph and things get rough. Feels like the vibration is in the front somehow.
Could this be a bad pinion bearing or something else in the rear end?
The steering wheel bounces and the whole car shakes. Mainly noticeable in the front.
The car doesn’t pull to either side so the alignment seems ok. And again, coasting at 60 feels like a new car.
After looking again, I don’t have confidence in my angle measurement on the pinion. I’m going to measure again from the yoke instead of the case. Maybe top and bottom and take the average. Looks to me like the pinion is still too low. I’ll try again and report back.
 

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After looking again, I don’t have confidence in my angle measurement on the pinion. I’m going to measure again from the yoke instead of the case. Maybe top and bottom and take the average. Looks to me like the pinion is still too low. I’ll try again and report back.
Yeah, if you look at those PDFs that I posted links to, they show you some places that you can take measurements from, and the diff case is not one of them...
The front face of the yoke, and the rear face of the trans tailhousing are the two easiest places.
 

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Discussion Starter · #31 ·
Yeah, if you look at those PDFs that I posted links to, they show you some places that you can take measurements from, and the diff case is not one of them...
The front face of the yoke, and the rear face of the trans tailhousing are the two easiest places.
Yeah, I knew I was fudging it a little on the pinion measurement and I think I was close but degrees matter. I could not get on the yoke because the driveshaft is installed. Didn’t want to remove it.
Here is the latest problem, according to qa1’s tech support the max length on this upper arm is 13” bolt center to bolt center. Well that’s a bit ridiculous in my opinion because the factory arms are 12 3/4”. That only gives you 1/4” of adjustment!!! As far as I’m concerned that is not “adjustable”. I’m dissapointed in that. And the fact the the max range is not published in their install documentation.
Im going to look at raising the transmission at the yoke today. If I have clearance to raise it I’ll make a spacer to go into the mount at the crossmember. Will probably have to get longer bolts too.
 

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Discussion Starter · #32 · (Edited)
So, I decided to make a spacer today to put between the crossmember and the trans support bushing. I looked everything over really good before I started to note clearances. That’s when I found a big part of the problem. The tail piece of the trans was sitting down on the crossmember. The support bushing was not supporting the trans enough. After a brief Yosemite Sam rant, I took the bolts out of the bushing and using a bottle jack raised the transmission. Checking clearance as I went up. I determined that I could only raise it up about 3/4” without things getting too close in the tunnel. So I made a 1/2” spacer out of aluminum. Making the spacer was easy. Installing it was a little nerve racking because I had to jack the transmission up a lot to get it in there because the bushing and the crossmember relaxed. The crossmember, even when taken loose on both ends can not be moved around very much at all. Any way after some fiddling I got it installed. Drove to the local Ace Hardware and grabbed some black flanged grade 8 bolts that were 1/2” longer and some new split lock washers (because you can’t over torque the bushing bolts) and installed them. Checked clearances again and took a test drive.
My angles are still not perfect but the combination of the small angle correction and getting the trans tail piece off of the crossmember have pretty much eliminated the vibration.
here are some pics of the job:
 

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Discussion Starter · #33 ·
So, I decided to make a spacer today to put between the crossmember and the trans support bushing. I looked everything over really good before I started to note clearances. That’s when I found a big part of the problem. The tail piece of the trans was sitting down on the crossmember. The support bushing was not supporting the trans enough. After a brief Yosemite Sam rant, I took the bolts out of the bushing and using a bottle jack raised the transmission. Checking clearance as I went up. I determined that I could only raise it up about 3/4” without things getting too close in the tunnel. So I made a 1/2” spacer out of aluminum. Making the spacer was easy. Installing it was a little nerve racking because I had to jack the transmission up a lot to get it in there because the bushing relaxed. The crossmember, even when taken loose on both ends can not be moved around very much at all. Any way after some fiddling I got it installed. Drove to the local Ace Hardware and grabbed some black flanged grade 8 bolts that were 1/2” longer and some new split lock washers (because you can’t over torque the bushing bolts) and installed them. Checked clearances again and took a test drive.
My angles are still not perfect but the combination of the small angle correction and getting the trans tail piece off of the crossmember have pretty much eliminated the vibration.
here are some pics of the completed job:
I’m not real tickled with that flimsy support bushing mount on the crossmember. I may buy an after-market crossmember and redo that later. But you can see in one of those pics that the trans tail piece is now not in contact with the crossmember.
 

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Yeah somebody has really hacked that crossmember.
I'm not sure if there's a difference between your tailhousing and my 4L60e, but the stock crossmember works on mine. However, the holes in the frame do have to be modified to use a stock one.

Bowtieoverdrives.com sells a crossmember that they say fits with the stock holes.
You should call them and verify that it will also fit the 4L65e... I think the mount location would be the same.
I don't know how the exhaust clearance is on it, you'd have to ask them if it accomodates exhaust that fits with the stock crossmember.
Theirs is only $239, which is about the cheapest you can find, as long as it has enough exhaust clearance.
Bowtie Overdrives - View Item
 
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