This morning, I did a bit more work on the wheel opening of the rear quarter panel in hopes of stopping the rubbing noise when going over large bumps.
I started out by measuring three inches down from the quarter panel onto the tire. This is to simulate the amount of total movement possible based on the distance from the rear axle to bump stop. This is shown below by the black line on the tire.
I then used a lug nut tied to a string to run a straight line down from the inner fender lip. The two silver marks on the tire and fender are showing where the string begins to touch the tire. These are the areas I will need to focus on removing material.
I then remove the wheel and decided to measure the width of the fender lip. This would give me an idea of the amount to remove. In the past when I removed material, it was from the essentially where the rub starts now forward. This can be seen a bit in the measurements shown below:
Somewhat below each measurement with a small arrow are updated numbers. The first set immediately below is what was accomplished through cutting and grinding. The second set of numbers is a small change which occurred from rolling the lip ever so slightly with a body hammer. My overall change is maybe 1/8" in most places which really isn't much at all.
With the wheel off, it is apparent the tire is also making contact just inside of the wheel well above the lip. The rub has removed all of the undercoating in the area. There is not much to do about this aside from a wheel with more backspace, raise the rear with new leaf springs, or a fender flare (not going there).
The trouble is that these wheels are not produced in this size with more backspace. There are a few others which are made but then I'm switching out wheels that I just purchased. I think I will go with new springs to raise the back up around 1/2". This should help and will not look bad. While I doubt it has an impact, I hope this will center the rear axle a little better as that might remove the issue entirely.
At this point, I don't feel bad cutting on the fender well area as I expect to replace the back quarter panels due to all the rust. Unfortunately, the hitting the inner lip with the hammer caused a crack in the paint. At least this all happened before painting the car.
02/16/2020 Update - I drove around today with my son and daughter in the car. I hit several larger bumps but never had the wheels scrape. I have, however, heard the tire go up high enough to hear it rub along the upper section of the quarter. While not great, that does not damage the tire and seems to have no impact on the quarter panel. I still plan on raising the rear just a little to help reduce this rubbing even further.
This morning, put the Mustang up on jacks and removed the front two tires. I started by cleaning up the suspension parts a little as they had grease and grime on them from the road trip to Tulsa. Afterwards, I moved on to the bulk of the work which was checking the torque of everything and greasing all the joints.
I removed all the cotter pins, removed, and then torqued all the steering pieces again just to make sure they are done right. There was a torn tie rod boot on the inner, driver-side tie rod which connects to the center link. Luckily, I purchased a set of Scott Drake tie rod boots years ago and didn't use them. Since I had a pack of two, I swapped both the inner tie rod boots out.
I found the bolts which hold the strut rods to the lower control arms were not torqued well. The rest of the bolts seems to be just fine although there were a few I put a slight bit of a turn on with the wrench. I figured now that I've driven it a fair amount it is best to make sure all is well.
I then purchased some Ford/Lincoln/Mercury grease at NAPA and pumped grease into all of the zerk fittings. Several took much more grease than I was expecting. Unfortunately, I found the boot on the driver side upper control arm must have a pin hole as it leaks grease out the side. If I replace the front springs, that would be a good opportunity to fix that if I decide it is bothersome. The part is a Moog K8142 and it is only about $20 on Amazon.
Since I had everything out, I thought I'd top off the steering box with grease. I checked StangerSite.com and followed his instructions to turn the wheel to the right, remove the fill bolt, remove the bolt farthest from the fill hole. I then stuck the end of the grease gun in the hole and filled until grease came out the bolt hole. Wildly, I pumped 120 times before grease came out the bolt hole.
The website also indicates you then turn the wheel to the left and then fill again. This time I was only able to pump the grease gun four times before grease came out of the bolt hole. I tightened everything up and called the job done.
What is weird about the steering box is for it to take 124 pumps of grease it must have been quite low. The steering box has 4,000 miles on it since being rebuilt in late 2011 by Stanger (Randy Meyer). As part of the process, he fills it up and you do nothing but install it. This makes me think he must have sent it without much in it. Thing is, it is hard to tell as when you take off the fill plug, you can see grease as the gears push the grease to the sides of the box so I always thought it was full.
I drove around and really did not notice a great deal of difference in the steering. I won't sweat it and just consider the maintenance done and move on.
My front coil springs are made by Eaton Spring and are sold by NPD as part number 5310-8. The springs are rated at 428 lbs to compress an inch at 11" tall. They were originally used on big block cars and on those with a 289 with A/C and the heavy duty suspension option.
When I originally purchased the springs, I cut a bit off at a time and ultimately ended up with 3/4 coil removed. At that point, I thought the ride height was about perfect. a few years later, while I had the engine out for work in December 2011, I decided to do the Arning drop which is supposed to lower the car a little. While I had the suspension apart, I cut another quarter coil off the coil spring for a total of a full coil removed.
As time has gone on, the car has continued to change. When the engine went back in, it had an aluminum intake and heads. In the last year, I added more weight back in with the air conditioning system and the big block style radiator. I can now only fit one of my two jacks under the front of the car as it is so low.
At this point, I think the front suspension is too low. I took the front wheels off this afternoon to inspect everything, I noticed the upper control arm is hitting the bump stop. I don't drive crazy but at times I hit a bump and there is a hard thud noise. I thought something was loose which is part of the reason I was checking but now I wonder if it is because the suspension is bottoming out.
I've not really considered how much space exists between the upper control arm and the bump stop. I put the wheel back on and rolled the car around a bit to get it leveled. It seems I only have about 2" of travel before the front suspension which is not all that great. From some quick reading, a street car should have about 2.5 to 3" of travel which would be measured at the wheel. With all of this in mind, I'm not sure if I bottom out or not.
For later reference, I decided to take a few pictures of the ride height with a measuring tape. The fender well opening is right at 24 3/8" at the highest point. The lower control arm is essentially parallel to the floor at ride height. I'm not sure how high I should take the front suspension but perhaps 25" would be good as that would increase my travel on compression at the UCA to 2 5/8". I'll continue to think on it as I save some cash for the parts.
While looking everything over, I noticed there was some play in the passenger side wheel. I'm not sure where it is coming from but it looks like the steering linkage. I'm going to see if I can't check the torque when I get everything a once over. For when that time comes, I dug up the torque specs...
1) Tie rod end to spindle arm: 30-40 ft/lbs*
2) Steering tie rod to center link: 30-40 ft/lbs*
3) Pitman arm to center link: 35-47 ft/lbs.
4) Idler arm to center link: 60-80 ft/lbs*
* Tighten to the low limit of the specification, then tighten the nut to the nearest cotter pin slit and insert the cotter pin.
There is a driveline vibration that I can feel mostly when slowing down but sometimes at other points. If I push in the clutch when the vibration is occurring it does not stop. This gives me the impression it is not related to the engine or transmission. My suspicion is that it is the driveshaft yoke or length.
It is unfortunately almost impossible to get pictures of the driveshaft and yoke installed as the vehicle is so low to the ground. However, I was able to get the following picture of the yoke in the transmission while at ride height. The worn section where there is no paint is .375" wide and represents the amount of movement occurring. Many say you need .75" free play at the transmission and I guess that is a safe number as it is double the movement I see.
The trouble is that after taking this picture, I disconnected the driveshaft from the rear axle. I then pushed it forward to see how far it would go into the transmission. The driveshaft slide all the way forward until the neck of the yoke touched the transmission seal. That is a total of 1.7" of movement which is way more than the .75" that is recommended.
I took the yoke out of the transmission and measured it. I put all of the measurements below so I can reference them and determine what I want to do. The best replacement part appears to be a Spicer 2-3-4871X which is identical except it eliminates the end of the yoke which has no splines. I'd planned to start by just replacing it until I noticed the driveshaft is way too short.
I then started looking into a new driveshaft and found a few different options:
1) I called a local shop to price extending my current driveshaft from 50" center-to-center up to 51" center-to-center. They said it would be $280 using my existing yoke and u-joints. This is rather expensive.
2) I've considered a Denny's Driveshafts replacement as it is a 3" aluminum driveshaft, new u-joints, and the new Spicer yoke. The tough part is that it is $450 but that is only about $100 more than the local price after I add a new yoke into the deal.
3) Some have purchased a stock driveshaft for a 2006+ explorer (4door, V6, AT, 2 wheel drive) and it is an aluminum version that is already the proper length. From what I understand, they are sold rather inexpensively. I'd have to add a yoke and new u-joints to the price as they use 1330 u-joints. I'd also have to play the local place to balance it which based on the other prices would still be at least $100.
https://www.vintage-mustang.com/threads/explorer-aluminum-driveshaft-fixed-65-vibration.910770/
I'm going to think on it for now as it is not horrible but is something I want to correct soon.
12/06/19 - After thinking on this a bit, I just decided to bit the bullet and get a Denny's 3.5" aluminum driveshaft. I then don't have to worry or think about it. It will just be done right. It will take about 4 weeks for them to build it so it should be ready around the beginning of next month.
