69 Rustang

My #1 learning about this Mustang occurred yesterday. When the gas gauge needle aligns with the line for “E”, it seriously means it is empty. Fortunately my wife was just a half mile away and could go home (1 mile the other way) and bring me the gas can. Doh! Lesson learned, next stop, the gas station! On the plus side, the rear end has been rebuilt—the center diff issues were covered in another thread, but it was a mess. Now the rear brakes are all new, new soft brake hose to the axle, fixed the axle vent hose, new axle seals, and one of the rear axle bearings was replaced. It is quieter than ever, especially when the engine dies from lack of fuel and you are coasting…. While waiting for the differential rebuild, I had time to start on the interior. The console has been disassembled, thoroughly cleaned and reassembled, the fold down seat mechanism has been cleaned and mostly reassembled (but out of the car). The dash has been cleaned up again. The trim has been transferred to the new door panels—when you buy the new ones and pay extra for the “improved” version, please realize they are still not a great part. At this point I am waiting on just a few things. The biggest delay is the headliner. I have a friend who has an upholstery shop and he is going to help fix my headliner—but between his schedule and mine we just can’t get together until October. There are still a few things I can work on though.

On both my 72 and on my 69, the heater/air conditioning blower only runs on high. Is the resister sold by NPD 19A706-2A the likely culprit?

All back together and first drive tonight—wow, the noise! Where was it because there wasn’t any! That is the quietest rear end I have ever had in a Mustang. Whew, glad that’s done. Now its time to get the interior put together!

A few pictures of the damaged carrier, and a few pictures of the restored differential. The first picture shows where a thrust washer used to be, it had worn away some time ago left behind is scoring and a huge ridge of worn material. The second image is the gear that was wearing on the surface in the first picture. The third picture is the other half of the carrier, notice the wear on the outer ring outside of where the spider gears are—it was grinding along here. So the noise I heard was because of the play in the spider gear/carrier assembly due to the missing thrust washer. All in all, I got lucky that my ring gear and pinion gear were not damaged. The other noteworthy comment is on the second picture. The spider gear here has four sections where there are no splines, so the 28 spline axle is only connected to 24 splines in the carrier. Notice the gap in splines visible at about the 12 o’clock and 3 o’clock positions. The guy doing the work for me said this is very common and almost always present in a 8” rear end, and it is uncommon but sometimes present in a 9”. He installed gears with the full 28 splines when he put the new one together for me. The last two pictures are the work of art I am going to install. Included with the overhaul was a gasket, copper washers, new nuts, and gear oil. Out the door for $420 including him swapping the differential case for one with a fill plug (which mine did not have due to someone changing it somewhere along the way).

I learned this is not the original center section to this car—this one doesn’t have a fill plug so it was changed somewhere along the way during life for one of the same ratio. If it was under filled, it happened before I got the car as it always had a clicking noise, but I never bothered with it as I haven’t put that many miles on this car to worry about it. I did pull it years ago trying to figure it out and put it back—that was when I realized there was no fill plug and I had to fill through the axle tube. I think I actually overfilled it as it leaked out and ruined the brakes on one side despite new seals. The guy doing the rear now is swapping out cases for one with a plug for an extra $50. The worse news is I have a second 9” center section with 3.50’s that makes the same clicking noise only it sounds even worse than the one I pulled from the car. So apparently I have two junk center sections! At least this one will be right when it is done.

The verdict: worn bearings and internal carrier damage. Need to replace the carrier and install new bearings. Hope to have pictures in a few days of the damaged bits.

We have a 94 Mustang GT in the fleet as well as our other Mustangs. I haven’t driven it a lot, maybe 200-300 miles since we bought it. Due to some current circumstances I am driving it frequently at the moment. Today I noticed the tach was jumpy. On the freeway, it was bouncing up 500 rpm over where it should be. The engine wasn’t revving or anything, just the tach needle. The fuel gauge was also dropping about an 1/8 tank, then it would come up. The other gauges were all fine the whole time. 5.0, 5 speed, 146k miles. Has new plugs, wires, cap about 150 miles ago. Any thoughts?

UPDATE: my son helped me pull the axles tonight. The bearings felt great and as I suspected, the left one looks brand new (the pressed on retaining ring is a slightly different color than the other side. So we dropped the center section out next, then shoved an axle into the center section and turned it: click click click click…. Then we got the spare 9” center section out and tried that one…guess what…click click click click! I had my son turn the axle while I used a flashlight to look at the spider gears and I couldn’t really see anything wrong. No metal in the housing, it all looks good. I think I am going to take the center section to a driveline shop and have someone look at it, I don’t recall any 9” doing this and I have 2 of them that do. The clicking is only on the drivers side.

The rear axle in my ‘72 makes a clicking noise. I tried to fix it years ago and pulled the center section—didn’t see anything wrong, changed the axle bearing (I am certain it was the left one, but it was a long time ago). As you can see in the video, when I turn the left axle it is really loud. The right side, not so much. At this point I plan on pulling the diff out again and taking it somewhere. It needs a new pinion seal anyway. The original is a 2.75 or so open 9” carrier. I do have another 9” center section, but the ratio is different at 3.25 and I would rather keep it stock. Any experienced thoughts on what you hear? 18F219E3-8D9F-450A-9214-8A16A21FC69A.MOV

The ‘73 AMX was my first car I noticed and commented on to my family as something I loved. I was about 5 years old at the time. That shifted to Mustangs over the next few years, but I always remembered the swooping fenders of the Javelin and late AMX’s. Excellent choice…you certainly like cars that are not the every-man’s car like a Camaro or 64-68 Mustang. By the way—auto crossing is a blast, but it is a bit tough on front tires as you tend to chunk them out at the edges. Better tire tech, the correct pressure, and better alignment angles specifically for the task will improve your results. I did it with my ‘69 back when it was my everyday/only running car. I tore the heck out of my tires and wanted to go more.

David, there were two pieces of lower stripe in the box, both the same length. This picture shows how far one stripe went. As you can see, it wasn’t even long enough to do the area from the front wheel well to the rear. I used both stripes in the box to get one side done, and then used a bit for just the rear of the quarter on the other side. I figured if there is some dimensional variation in the next set I get it won’t show from the front of the quarter panel to the rear. Fingers crossed anyway. For the textured black, I’m not sure who makes it. I like the smooth look anyway so I wouldn’t have used it. I’m not worried about a concours event. I did start with your dimensions when laying out the hood, but rather than different measures on one side versus the other and the original, I couldn’t help myself but make the measurements side to side symmetrical. That said—what a great document you prepared, I would have been guessing without it. Thank you! One knowledge gap is how the lower stripe “finishes” at the back of the rear quarter panel. Does it wrap around a little…get cut off straight? I made my own decision and went with it. But if you have details that could be your next article/white paper.

Been a while since I updated, so here goes. A bit frustrated at the moment. I started putting stripes on today—right off I screwed up and put one of the door stripes backwards—picture below. I am blaming the graphic reference I taped to the window—ha ha. Had to peel it off and now I have to buy another kit. Then I tried lining up the lower body stripe kit and realized they don’t give you enough stripe to do the whole car, it takes 1 1/2 kits unless mine was missing bits. Calling NPD tomorrow on that one. I did manage to get one side fully and correctly striped with the hockey stick and Mach 1 emblem. I did the hood blackout yesterday, it turned out pretty good. Based on my experience with the PPG Hot Rod Black it will dull up a bit more over the next few weeks as it cures. Picture of that below. Otherwise body assembly is done and I am waiting my upholstery kit. It turns out a buddy of mine has a connection with the company that manufactures the kits so he is going to see what is going on for me. The car is turning out really nice, and after putting the hood blackout and side stripes on, Wimbledon White is looking pretty good. I know I expressed a lot of concern early on, but it is going to look sharp.

Congratulations, now you will know what being busy really means!

A productive weekend, I applied the lower blackout paint (I know out of order based on how Ford did it). But it turned out really well. Once that was done I put the front and rear valances on, installed the rear bumper, the rear honeycomb, gas cap and license plates. I still need to find some clips for the rear honeycomb upper and lower moldings, I bought a hardware kit for this but bought the wrong one as it doesn’t have the clips that go in the moldings. After reading the description of the hardware kit, it doesn’t sound all that great given it is $26 and they state the clips are too short right in the description. Thinking about getting the hood ready for blackout, the other stuff turned out so well I am ready to get it done! Pretty soon, I am going to be just left with the interior overhaul. I already ordered seat covers and have decided to order new door panels too. That makes everything new or reconditioned in the interior as the headliner and carpet were recently replaced and the dash has already been overhauled. Unfortunately the seat upholstery is still 3 months out on some sort of backorder. There is a finish line in here somewhere.

Yep, first thing done is to paint the lower color. I broke protocol—today I painted the black on mine after having painted the white a month or so ago.