As some of you might know, I recently installed an 8 3/4 rear axle out of a 1969 Plymouth Belvedere into my 1984 Chrysler 5th Avenue. The swap went swimmingly and all was well for two days. On the third day the driveline began vibrateing fiercely at speeds over ten M.P.H.

I have since discovered that the pinion angle on m yrear axle is wrong. The "nose of the axle is pointed up in the air, visible without any devices to measure the actual degree. I obviously need to add shims to bring the nose of the axle back down into the negative degree area (as measure from level).

Tis morning I went to a local spring shop and got some six degree axle shims. This was the largest degree rating they would sell me. I figure that since Mopar recommend 5-8 degrees negative for the pinion angle that a six degree shim should be about what I need.

MY QUESTION:

Do I just plop these shims on top of the leaf spring and below the rubber in the M-body Iso-clamp system?

Will I need to use a longer locating bolt to keep the rear axle located properly or can I use the existing bolt in the rear springs?

Thanks in advance.

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Casually looking for a Clifford hyperpak intake for cheap.

I don't know the answer to your question Reed, but you might also check out www.dippy.org
I don't own an M-body, but I'm registered there anyway, and I've found the folks there to be helpful and friendly.
I know that at least one of the guys there has done the same swap as you.
Good luck, I hope you get it worked out!

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"Ja, Ich fahre ein altes auto."
'78 Volare 225
'67 Charger 318

Thanks Wes! I consider the F/M/J cars to be the same anyway, since really they are...

I will give it a shot.

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Casually looking for a Clifford hyperpak intake for cheap.

Reed,

This is one adjustment I found best left to a knowledgeable shop. I found that truck rear end shops are well set up to adjust pinion angle. of course all tires have to be on a level flat so the vehicle is level. The reason I didn't do my adjusting and paid $25 to have it done is that I discovered "pinion angle" didn't mean to me what it did to a shop. It is kind of like reading an insurance policy and thinking you know what exclusions mean.....why it is just plain English, right?

rock
'64d100

Rock- that is good advice, and I may yet just have the spring shop do it. If this gets to be anything more involved than sliding the shims under the axle then it is going to a shop to be done right. The last thing I want is for the rear axle or driveshaft to fall out while I am cruising down the highway....

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Casually looking for a Clifford hyperpak intake for cheap.

6° is almost certainly going to turn out to be wayyy too much. Review my earlier post about putting 4° in D'Valiant. This really can't be eyeballed; measurement is necessary. I agree with Rock — see if you can get a shop to set it up.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

I am thinkning I might do that since I am running into trouble figuring out how to getthis to work with the iso-clamp system. Grrr. Tiem to take it in to the spring shop I guess.

Thanks guys!

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Casually looking for a Clifford hyperpak intake for cheap.

Well, the advice I got on Dippy.org was that I shouldn't shim it and should replace the rear springs instead. Apparently shims don't work well with the iso-clamp system and the bad pinion angle is likely due to broken/worn springs.

Joy. Another $200. I will have spent as much on this rear axle as I did buying the car by the time this is finished....

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Casually looking for a Clifford hyperpak intake for cheap.

Reed,

A little late, but look here

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

I found that, but the $87 price tag made me choke. I spent $30 here in town for the shims, before I decided to just bite the bullet and ordered new 5 leaf springs from JC Whitney. $140 with second day delivery isn't too bad, but if I ever sell this car or it gets wrecked I am pulling this rear axle and keeping it on general principals.....

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Casually looking for a Clifford hyperpak intake for cheap.

Hummm...
Is that because it has been a major nuisance?

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

No, because I will have spent as much on the rear axle as on the rest of the car and it is almost completely rebuilt and new.

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Casually looking for a Clifford hyperpak intake for cheap.

Reed,

I used 4 degree shims on my 8 3/4 swap. Mine was from a "C body" I tried 2 degrees and it still vibrated. One thing you need to do is get rid of the rubber isolaters. They will allow allot of movement too. I found that dialing it in with a stainless steel bevel gauge and level made it pretty easy. You are always suppose to change the "U" bolts and not reuse the old ones. The shims I purchased were solid aluminum so I had to drill a pilot hole for indexing. Once I dialed it in, it's been 3 years ago, it drives smooth as silk. It is funny how much difference a few degrees make.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Thanks Ted. Unfortuantely, I am stuck keeping the iso-clamp system right now since I don't have time to go find the parts necessary to eliminate it. Plus I like the soft ride anyway.

I just can't figure out why the car drove fine for two days before the shimmy developed. THis makes me think I lost a weight on the driveshaft or one of the new u-joints I put in went bad. I am going to take the driveline to a driveline shop next week and have them check the bearings and balance the line. I am crossing my fingers that that will fix the problem. Otherwise, I need to order another leaf spring from JC Whitney (yes, I mistakenly assumed they only sold them by the pair , my bad) and rip the rear suspension apart again.

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Casually looking for a Clifford hyperpak intake for cheap.

Jezz Reed, that thing ain't no Corvette there Bud...

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC