Exorcising a '78

The gears have 40,000 miles on them. This car was a v6 and owned by a retired couple for those miles. I think they would be fine. Although I have read its hard to make the gears re-mesh and be quiet when changing the carrier. The old pattern is already worn in and hard to make quiet again. How true that actually is I don't know but my luck is that even if it happens very rarely I will without a doubt be in that rarely group.

This car started as a "use the parts bin and make her run project." That just cost more time and the money to do it right after using the cobbled together/ inexpensive route and :poo: failed repeatedly. Pricing out rebuilding mine or getting a rebuilt pumpkin is not that much difference when including gears and tru trac. Factor in no down time with complete pumpkin it is a difference of a few hundred going like for like. Upgrading to a new case and aluminum pinion support makes it about $500.

In my mind a rebuild only makes sense keeping the 3.40's but they do have wear and it sounds like I would be happier with a 3.55 or even 3.80. hmmm. decisions decisions.
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I'm not so sure about the gears making noise when switching carriers, I think that's an old wives tale. It may have been true way back when with different manufacturers or whatever, maybe their heat treat wasn't as it should have been? :shrug: BUT, I just replaced the open carrier in my Ram with a TrueTrac and I don't have any problems. I also reused the ring and pinion in the 8 inch in the Cobra, no noises there. I really don't think you'll have a problem as long as it's set up properly.
A Ford V8 enthusiast in Austria (I know him from a german forum) is rebuilding diff carriers in his spare time. He always says that original ring&pinion (if in good shape) are better quality than today aftermarket stuff... :shrug:
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Finally got her back from exhaust last night. Starter was still hanging up causing all kinds of noise. I drove it home the long way which is about 4 miles. Vibrations galore. low speed, high speed. Weird noises when using clutch. Ugly shudder when downshifting.

Pulled starter and checked tooth count. It has 9 teeth. Compared it to my old starters that worked. They appear identical except the old starters have a 1/8inch or so bushing at the end of the starter shaft that appear to stop the gear from going as deep. I cut up a truck block plate and made a shim for the starter. She now starts and disengages at it should.

Figured out how to actually check pinion angle. Used the phone app and a irwin angle finder. I was 0.7 off. Well within spec. Reading about multiple people doing a t5 swap have to raise back of the trans I made a spacer for trans mount. It made the pinion bounce and vibrations horrendous on jack stands. So I pulled the spacer out and left it at the 0.7.

Considering our engines are offset to the right by an inch could that angle be off causing me grief? I tried moving rear of trans left and right. It only moves about an inch but it made no difference.

Pulled the rear tires and axles to help rule out vibrations and to be safer under it while in gear on jack stands. Fired it up and put it in 2nd. The whole driveline is vibrating. This time it seems to be coming from the front of the transmission. I could hear all kinds of racket from starter/bell area once clutch is engaged. Pushing in the plutch noise goes away. Looking into the clutch fork access the pressure plate and throwout bearing are bouncing and wobbly. The pinion is not bouncing like before. I can feel a rythmic hitting from differential to the bell housing.

Sigh. This is so frustrating. The vibration felt similar on the drive home but looks different underneath the car. I have swapped out everything but the pumpkin. Tomorrow I will pull the trans again to try and figure out what I did wrong installing the pressure plate. I have installed multiple clutches over the years. I used a torque wrench, star pattern, 2 steps on the torque setting but it was only 20ft lbs iirc. The instruction stated it did not need the locating pins because they sent shoulder bolts. That is the only thing I can think of that was different.

Stay tuned for the next installment of "What the hell did I get myself into this time"
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FYI I had trouble getting trans to seat the last 3/4 inch. Pulled it apart to recheck everything and found the pilot bushing very tight. I had a rad4 laying around and pulled it's input shaft to use as a test fit. Had to smack it a couple times then pop it out. Did that 3 times and trans went together.
Perhaps there is your issue. If it is a solid brass bushing it needs to fit tight. It is easier to get in when you use a modern needle bearing.
If your bellhousing is warped or not centered to the crank shaft this all will ad up and your input shaft will never be "drag-free", but it is bushed to one side.
Did you check the bellhousing in regards if the bore where the transmission is positioned is centered and in plane?
I will hopefully have time later today to see what I messed up. With the way the pressure plate was wobbling my best guess is the bolts backed out. That also explains me thinking the vibrations improved but as they backed out it got worse.

I have to use an extended pilot bushing. It was custom made by MD for this application. When I first started it up the rear tires would roll in neutral unless on the ground or brakes on. Now the bushing is wearing in some they barely moved.

I did not check the bell alignment. This exact combo, engine/ flywheel/ starter/bell and clutch all worked with my rad4. No vibrations. No 2nd gear and 3rd gear was knocking but it was smooth in the old rad4. Just really tall gearing going from 1st to 4th. lol

I initially reused the clutch flywheel and bell for my t5 conversion. Immediatly the pinion started bouncing. I have had the pinion angle checked by 3 shops. One a performance shop that built race cars for years. Another a custom hot rod shop near me. Assumption was it internal to the used t5 trans I installed. That has now been replaced and the vibration just moved from pumpkin to bell. WTF.

I now have a new clutch/pressure plate and flywheel. Either they have a defect or I screwed up. I am thinking the 20ft lbs is no where enough to hold that pressure plate. It was in the instructions but iirc it's usually 30ish ft lbs.
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Sounds like you will find the issue soon. :nice:
If you worry about the bolt torque, the late model 5.0 HO pressure plate to flywheel needs 12-24 lb*ft (metric M8 thread). And if i remember correctly there a four bolts that hold the pressure plate.
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If you're worried about the bolts backing out, add some Loctite to them. The medium strength stuff should suffice. You can also add lock washers if you've not done that. That might actually solve the flywheel/pressure plate issue and kill 2 birds with one stone.

You said your pinion angle was out by .7? Is that in degrees or...? IIRC, pinion angle needs to be -2* when static so when under load it comes into phase. There are a few different threads in this forum alone that talk about that - hell, I created one way back when! If you do a search and locate one/any of them, there should be some different links and explanations about pinion angles, etc. Here's mine:

Speaking of old posts...... I wonder whatever happened to @Wart :shrug:
Must've gotten mad as hell and decided to not take it anymore.... :jester:
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I could not find anything amiss until I pulled the trans. As I was pulling it the pilot bushing fell into the bell. Don't remember ever having one come out that easy. Once I got the bell off I found the steel sleeve and the bronze bushing laying in the bell. The sleeve is blue from heat. It looks like the bushing was too tight on input shaft and was spinning in the sleeve. Or the sleeve was spinning in the crank. When I placed my order I bought two complete clutches with pilot bushings. Comparing them side by side the new bushings are different from each other. One has a shorter sleeve and offset bushing. They appear mechanically similar but different iterations. Both are very tight on input shaft but slide into crank easily now. When I initially installed this bushing I had to use a pilot bushing tool. It used to be tight. The pressure plate bolts were all still tight.

Luckily I had two bushings made when this project started many moons ago. I had to buy a 4" piece of oillite and since they had it mocked up for the shorter input shaft and there was going to be extra I had them cut a longer and shorter bushing. Just in case I upgraded to the sn95 shaft. It fits the input shaft just fine. No play, just slides on all the way and spins easily. My one concern is that it slides into the crank now. Easily. There is about as much resistance in the crank as on the input shaft. This is what makes me think the old one was spinning in the crank. I used to have to knock in the bushings, now they easily slip into crank.

Now I have a significant oil leak from the rear main seal. May be the pan but I resealed it last fall with the one piece fel pro gasket. I did not notice a puddle under it but this morning I ran it before I started and several drips came from rear main seal area. I am hoping its just from the vibrations and will stop when I get this fixed.

Reinstalling the trans was snug but I was able to get it fully seated by hand. It's tight but no crossmember instyalled yet. I ran out of time this evening. Hopefully an hour or two in the morning and I can test it and see what else needs fixed.

I used the tremec app for that number. I believe it indicates 0.7 degree difference. The app showed that number in green and said I was within spec. Using the Irwin angle finder I could not see a difference in the angles. It's analog so hard to discern a degree but backed with the app I hope it's right. Although in my heart I think thrust or pinion angles are off. That is why I have had her at several places and yet all 3 say it's fine.

Hopefully I am cruising by noon tomorrow. Otherwise I may have to pick up a for sale sign or 8. lol

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I am at a loss. Clutch is fixed. That noise and vibration is gone from bell housing. YEAHHH!!!

The Rear main is still leaking. BOOOO

Worst of all. The friggin 1800 rpm in 5th only vibration is still there. All this money and time spent and no resolution. Not to mention the honey due list. Now that I have a speedometer it starts at 58 mph and gets rough by 62 then doesn't go away but seems to happen so fast you feel it less above 2200 rpm or nearing 70. Any other gear is smooth through that rpm range. I did not run 4th to 60 as they are resurfacing the roads on my usual test route and rain is headed our way.

Axles and diff are all that's left of the drivetrain. The axles were redone by moser. Wheels and tires were changed. Open diffs usually don't cause vibrations unless they are really messed up. I pulled it and looked it over when I changed the fluid last spring and it looked fine. So I pulled the pumpkin out the blue cobra. It's oil soaked from the pinion but the fluid actually looked fresh. I think I am going to swap that out just to see. That will probably be a few days before I get around to it.

I believe it's angles being off. I am going to call around and find a frame shop or custom fabricator who can check it. I tried last spring and no one wanted to touch it.

I probably need to look up some kind of lazer I can shoot lines under the car and measure off them. hhmmmm
You said you didn't see a difference in the angles from the transmission to the differential yoke? I'd try to add an angle shim to the leaf spring mount to angle the pinion down a couple degrees. I'm quoting Wart's comment from the thread I linked and highlighting some of it concerning this. After shimming my axle like this my vibrations all but went away. I still have one at high speeds, but it's nothing like it was when I first swapped the transmission. It seems like I shimmed mine 1-1/2*, but I don't recall for sure now. But if you think it's still an angle problem, this would be a good place to start.


1) When measuring this the cars rear suspension needs loaded as though it's sitting on the ground. The rear axle needs set on blocks or stands or the tires on blocks, the front wheels need to be on blocks or the front held by stands on the cross member (on a line between the spindles). I've had the back on blocks and the front frame rails on stands in the header area and notised when lifting from the cross member the rear pops up or down when coming off or going on the front stands.

2) as has been stated, the inexpensive inclinometers arent to be trusted, Their repeatability needs verified. IE: Mine will read 1 ~ 1 1/2+ degree different depending. IE #2, If I measure from the tail shaft of the trans and the measurement is 1 degree off true, then rotate/spin the gage 180 deg and measure the rear and it reads 1 degree off in the other direction it's actually reading 2 degrees off. :shrug:

3) Unless measuring from the machined surfaces of the yoke your probably not getting a good reading. I don't remember seeing a factory yoke with other than the cap surfaces that could be considered measure worthy. So you need to seat a set of caps in the yoke, or figure another way to measure from the machined surfaces.

I get the tail shaft angle from the front belt pulley/dampener. Luckily I have a 2' steel rule so I can drop a parallel measuring surface about 14~16" under the pulley. Any straight and parallel item of sufficient length will work.

Doing it this way I can measure from the "right" in the front and from the "right" in the back and inaccuracies in the inclinometer matter little if any.

4) Then that would be 3 down 3 up so then I guess that would be the ideal situation.

Um, Yeah, that is called 'in phace' and is the ideal situation with a car in motion. Not at rest.

The force needed to move the car rotates the axle causing the pinion to climb.

When you start in phase the pinion rotates/climbs out of phase. I did this ... once. At 55 the rear end banged/slammed so badly it sounded like it was going to come up through the bottom of the car.

So you want to set the pinion "low" so the axle rotates and the pinion comes into phase.

In an ideal world when the pinion comes into phase the trans shaft, drive shaft and pinion would be in a perfectly straight line*. :rlaugh:

How low to set the pinion ... I believe the figures are ~ 3 1/2 degrees for a 'street driven' car, and up to 7 degrees for a purpose built straight line car. Of course this only applies to leaf springs.

* One of the things that make the "straight Line" a laugh is the IIs drive shaft isn't "straight'. The 'shaft' doesn't leave the trans at 180 degrees nor enter the rear at 90 degrees. Thus there will always be a measure of vibration. The best you can hope for is to minimize vibration.

I believe that's why the II came with soft engine and trans mounts and rubber freaking mounted rear ends.
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Using the angle finder the pinion was 2 down and the tailshaft 2up. It was hard to use but had a slider I lined up on rear and switched sides up front to reverse the gauge and it pointed to same place. I do not remember specifics of tremec app but it was 2 something both times. Down pinion and up tail. Then popped up 0.7 difference in green.

I have read all that and then some. I have spent the better part of a year reading various ideas. And as usual I always pick the worst route first. lol. With the shops telling me it was in spec and the T5 was at fault that's the choice I made. I am just gonna order a couple angled shims and see what happens. If that fails I am looking into a cv driveshaft. Found a hot rod article on it fixing a vibration. They can deal with 10 degree without vibrations. Just sent them a message to get a quote.

It's drivable now. Just have to keep her under 50ish. The shifter feels much crisper. I am not embarrased every other time going into 2nd when it would grind. I can actually downshift to 2nd. I like the 2.95 first gear. It's more usable. Clutch feels just like stock. Firm but not so much it's tiring. I have a way to get replacement starters easily. The new to me headers seal up much better. So, it was not all in vain.

Plus I can see at night! Not too fond of the modern lights in general and white ring specifically. My intention was to delete turns in grill and use rings as turns. Hard to see yellow rings when headlights are on though. So I don't know. Any opinions?

Hopefully you can get that vibration taken care of - or at least make it so it's a lot more tolerable. (Insert fingers crossed emoji here)

So I watched the video, I was wondering how you went about adjusting your headlights? The look like they're pointing kinda low to me, but it could just be that I'm so used to driving my truck at night that it's misleading. When I replaced the headlights in my truck though, I had to adjust them since they were pointing at the sky. So I looked up the most appropriate way to do so since I didn't mark a wall or anything before I took the stockers out. I found a YouTube video (go figure, right? lol) that explains it. Basically, there should be a mark or something on the headlight that symbolizes the center of the light. You park the car on a level surface that's 25 feet from a wall that's perpendicular to the surface and to your car, mark the same distance up the wall as that mark on your headlight is from the ground, then aim your headlights so the beam is just touching your mark. Here's the video if you're interested, it goes into far more detail than I just typed.

View: https://www.youtube.com/watch?v=GWvSWBlAwnI

I really need to take my car out and get this done with it, I know they're aimed high. But I can count the number of times I take it out in the dark on one finger. That and with the number of people who drive with their high beams on around here kinda make it a moot point.
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Initially I aimed them at the door and got them what I thought was close. In reality I just keep turning the adjuster a little here and there. When I first got her running we were out late with the old halogens and I had the lights so low it was scary. Each time I have had her out at night... 3 times or so. I keep bumping them up a little. Now that I have these lights it's like night and day already. I should have hit the brights in the video. My only regret is I should not have gotten the halo rings. They would look better on a car with chrome accents.

If you still have the halogens any older shop should have headlight aiming tools. They suction cup onto the glass using the 3 nipples in the glass as alignment mounts. I havent seen them in a few years but those little nipples were around for decades.
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I have been waiting to write this as I wanted to give them a chance to reply. I just think 3 weeks is plenty of time to reply.

I spent $4,000 with Modern Driveline. I purchased a new trans as well as parts to convert my old t5 to sn95 input shaft. 2 sets of clutchs and pilot bushings to install the new trans in t top and old trans in my sons car after a rebuild. They have ghosted me for 3 weeks now that they have my money. I did receive mostly good parts but had a few problems. They initially asked me for more info on what I received. When I gave them the parts numbers and told them the ball fits a 5/16 bolt they just dropped off the earth. I have emailed the salesman a couple times and forwarded our e mail chain to the owner. I have heard nothing back since October 6th.

I ordered a shift ball and shifter handle. I received a 3/8 shifter handle and a package labeled 3/8 shift ball. The ball actually has a 5/16 thread and will not fit the handle. They sell a II specific kit. It includes a straight shift handle that is too tall. It puts your knuckles against the radio. I changed it to a curved handle but 8" is the shortest one they carry. II's need about a 5" handle.

I attempted to purchase an sn95 length input shaft for my old 1990 t5. They quoted me $500. I found one for $75 online and asked them why theirs was so much. They said they made a mistake. The 3.35 gears input is $75 but the 2.95 was $500.

As noted in a previous post above the pilot bushings do not fit the input shaft correctly. Both parts are custom made by them according to them for this application. Yes, I messed up not pre fitting their parts made for each other together. I trusted them to do that right. Now I know better.

I have horrible luck when it comes to these kind of things. This is probably a one off experience but I thought you guys should be aware of it. If they ever do get back with me I will post the resolution here.
You are right. They are not cheap. They are the only one with II specific parts though. Anyone else I would have had to open trans to swap at least the bearing retainer voiding the warranty. They did that in house for free since I had to purchase a II retainer and the $500 input shaft. As you can tell I feel a little sore about paying that. It was tolerable when things were going well. Not so much now.

During the sales process they were prompt. All the way to the shift ball being wrong it was good. As soon as a problem arouse they went silent. Just baffles me. The sales guy knew I had other II's and still need another flywheel and cross member at minimum. He knows I was talking about the build here. He knew I wanted to change to a curved handle due to Enzio's experience.

I am hoping they are just busy and I will get a shift ball that fits and a replacement bushing. 3 weeks of no contact though seems excessive.

In hindsight I should have gotten just the handful of parts from them and had my transmission guy put one together for me. He has the old T5 now. I wanted a package that was as turn key as I could get to get rid of the vibration.

Could have, Would have, Should have. Just another one of life's reoccurring themes.