I installed the oil slinger and adjusted the solid spacer thickness to get 25 inch lbs. or rotating torque with new bearings and the pinion seal installed. I've checked this one enough with and without a seal to know the seal adds 5 inch lbs. of rotating torque. The rest should be straight forward.
Yeah, still reinstalling the 3.89:1 gear set. Bottom line for the decision was the performance with the 3.70 gears combined with a close ratio trans was noticeably worse. So its not a complete waste of time even if I end up looking at the trans to find the noise. At least I had the foresight with the exhaust to make it easy to remove the front section for access to the trans.
I only found small issues with the 3.70:1 gear set when disassembling it. Tooth contact pattern was a little strange and the ring gear was no longer snug on the carrier. The ring gear is supposed to have a slight press fit on the carrier. The 3.70 ring gear fell off after I removed the last bolt.
My only question with the trans is does it have the correct input shaft. The trans is from a 1968 Mustang or Ranchero with a 390. The 390 input shaft and 289-302-351W input shaft are both 1-1/16" dia. with 10 splines. However, the tip of the 390 input shaft that goes into the pilot bearing is 3/8" shorter than on the 289-302-351W input shaft.
When the trans was rebuilt the shop told me the input shaft needed to replaced. I said okay and they installed a new input shaft. I hope, again I hope, they recognized it needed an input shaft with a longer tip for a 289-302-351W. I wasn't aware of Ford's input shaft differences back then. School of hard knocks again.
All I can add to that is I've had to jiggle and rock the motor and trans to get it together that last 1/2" or so. In a couple of pictures I have with the trans installed and no motor, it looks like the longer tip on the input shaft. Lastly, I don't have any strange vibrations, oil leaks from the front of the trans, or clutch chatter.
After getting this rear axle back together, if the same noise is still present, . . . the others here would have been correct and I will be pulling the trans. Fortunately, aside from the weight, that's not too bad. A few hours work to get it out. The parts are easily available new and not too pricey either.
If I drove this car more often I would recognize when anything different or unusual pops up.
Okay...it is very normal to wiggle, jiggle, and throw out a few cuss words to get the transmission to fully seat into the pilot bearing. So I don't expect anything out of the norm in regards to that.
If you want to make the job a little easier you can make a set of guide pins and screw them in by hand into the two top holes of the bell housing. They can be made from two old head bolts. Just die grind the heads off. Then all you have to do is lift the tranny onto the guide pins and slide it in. You will still have to wiggle and jiggle the transmission but you should not have to use cuss words!
By the way, did you happen to specify to the transmission shop that the transmission was going into a small block?
If you have a few pictures of the tip of the transmission input shaft I will take a look at to see if I can differentiate what input shaft you have.
The trans was rebuilt back in about 1997. I don't recall what I told them. I'm going to look again for the receipt. It might have a part number or description on it.
The pictures I have are not digital and I don't have a scanner that can digitize them very well. Otherwise I would upload them.
Another variable thrown into the equation is I am using a roller bearing type pilot bearing. It is for a late model Mustang with a 5.0 motor and came from a Ford dealer parts department. It has the correct inside diameter. I did check fitment before installing it into the crankshaft. But, it doesn't install as deep into the crank as the older bronze type pilot bushings. The roller bearing comes inside a soft steel bushing. The soft steel bushing presses into the crank and has a shoulder at one end. So it only goes in until that shoulder contacts the crank. Even if my trans has the wrong input shaft it might still be going into this pilot bearing.
I know they sell, or used to sell, a modified bearing that would fully seat into crank but extended further to accommodate a big block input shaft on a small block application. That said, I have heard mixed reviews on them.
Personally I prefer the solid bearings over the roller bearings. Less moving parts the better if you know what I mean.
Listen, with the rear end and drive shaft out of the car it is very simple to remove a few bolts and slide the transmission back and take a peak at which input shaft you have. I wish I were your neighbor because I would be right over to assist you. The two of us together could have the answer in 15 minutes, possibly less.
I too have thought of sliding the trans back while it's still up on jack stands. I might do that. I think it will take a little longer than 15 minutes because I need to get the exhaust out of the way. But, still not bad.
I went with the roller bearing for a pilot on advise from a local Mustang shop that sold parts for and repaired only early Mustangs, Mustang Ranch (NOT the place in Nevada). I also thought, its a Ford OEM part and Ford is using it on production cars so it probably works fine. I also remember from when I was younger the input shafts getting worn from the bronze type pilot bushings.
I can never argue against OEM parts. I guess it really just personal preference.
You are correct, I forgot about the exhaust system being in the way. My Mustang set up is pretty simple because I do not have an H pipe to worry about. I have 3 bolts at the headers and 1 bolt for a hanger and it's out. Literally less than 10 minutes to remove my entire exhaust system.
It is worth taking a look to see what you have up there. At least you know. I am keeping my fingers crossed it is the correct one.
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