"Doc's" new 9" inch
Posi-Traction Rear End
&
PRAISE DYNO BRAKES
I ordered this rear end from Delta Mustang located in California. It is a new
reproduction replacement housing that they build to duplicate the original Mustang
rear end, to include the step-down necks on the ends. This allows the use of the
correct original U-Bolts and bottom plates. I paid $350 plus shipping for this
housing. Delta Bay Mustangs http://www.deltabaymustang.com/
Phone: 1-800-664-8350 I spoke with Tom and he was most knowledgeable and helpful.
NOTE: the prices on their website are NOT correct, they are old and outdated.
As you can see it came primered so I had to paint it. It also requires that you round
up all new bearings and seals for it as well, which has been a wild goose chase as
well. AUTOZONE only had 1 correct seal and so I had to chase the 2nd down.
They had the correct bearings in stock at AUTOZONE.
Here are the new gears for it. They are reconditioned 3:70 posi traction gears
that Delta Bay built for me. They changed the output YOKE to match up to the
universal joint on my existing drive shaft as well. Although I haven't done it yet,
I am told that I will be required to shorten the drive shaft by about 1" in order
to complete this changeover. The gears cost me about $675 from Delta Bay Mustang
and they arrived promptly.
Here is my new Currie Performance axles. 28 spline with bearings and seals
to go into my new rear end. I ordered then locally from a drive shaft shop
and they ran me the same as ordering direct from Currie. They were $445.30
with tax, which is about what the shipping would have been and no tax, so it
figured about the same from MESA DRIVE SHAFT SERVICE.
Here is the new drive-shaft SAFETY LOOP. I am somewhat disappointed with it
since I paid $25.00 for this one, later to find it offered elsewhere for 1/2 that. Oh
well. Live and learn. Right! It pays to shop I have found out.
Here are my new Traction Bars. I ordered these from
http://www.ponycarstore.com/advscripts/shelby.asp
I might add at this point that the Pony Car Store has some decent
products good prices and good customer service (EXCEPT their
shipping system takes FOREVER to get things from them.)
Here are my Frame Stiffeners from
PRAISE DYNO BRAKES-
Praise Dyno Brake's all new Cryogenically Treated technologically advanced
STAGE-III Brake System includes Semi-Kevlar brake shoes, Thermo Cooled
composite Finned brake drums, high volume wheel cylinders and heavy trick
spring kits. Independent tests have shown that their brake systems stop as
much as 38% less than O.E.M. brakes and costs hundreds of dollars less than
disc brake conversions. A direct bolt on with no other changes, yet much improved
stopping power. The (2) Finned rear drums, Kevlar shoes, springs and high volume brake
cylinders cost $437.90 including shipping to me. Praise Dyno Brakes (972) 636-2722
Realizing that with the disc brakes up front and the use of the adjustable Kelsey
Hayes Proportioning Valve I currently have, I would not benefit much in stopping
power by going to rear disc brakes or even larger drum brakes. For these reasons
I chose to simply upgrade to the Praise Dyno Braking system. Which should be
more than sufficient!
THE ASSEMBLY:
For this part of the project I commissioned my old friend Glenn Gibbons owner of
East Valley Muscle Cars, who has done numerous jobs for me in the past on some
of my other cars. http://www.dgiperformance.com
As you can see from his "wheel standing" Poncho he knows how to build rear ends
that will hold up to some pretty abusive use.
Glenn started putting all this rear end stuff together and then I got a call from him.
He said, "Hey Doc, the rear end housing is 1/16th of an inch too short!" "The axles
are bottoming out in the center gear pumpkin. What do ya wanna do?"
I said, you have choice, since I am not going to send this stuff back, for just a 1/16th
of an inch. Either make a spacer so it will bolt up or grind off 1/16th of an inch off
the end of the axle that's too long.
I hate it when that happens! He ground off the end of the axle and it went in and bolted
up just fine.
As we start to finish up this project I realize that I had neglected to get new
brake line tubing for the rear end as well as the center flexible brake line. So I
went shopping again by making some inquires on VMF for some advice and
ended up purchasing new stainless steels and a new stainless steel flex brake line
from http://www.classictube.com They shipped them out Express Federal Express
and I got them shortly. For a tidy $77.00 plus shipping.
and 
Here's the FINISHED rear end! Finally!
(click for enlargements- NOTICE the new Traction bars to be welded in)
Here's the old 8" inch after it was removed. We had to steal the bolts of the old rear end
to use to bolt the axle housing to the backing plates but other than that, everything else
is new. Including new emergency brake cables, brakes, lines, wheel cylinders, drums,
you name it! Including new U-joints....which is another story. Read on...
The DRIVE SHAFT:
We got the rear end all done. Installed it and had measured the drive-shaft to make sure
it would be the correct length (since I had originally been told by Delta Bay Mustangs that
the drive-shaft would need to be shortened by 1" going from an 8" to a 9") WRONG!
It turns out to be the same. No need to shorten the drive-shaft. BUT....
Naturally I wanted to start out with new high quality U-joints and also have the drive-shaft
properly balanced. So we sent it to Mesa Driveshafts to get refreshed. A day later it came
back (along with a bill for $165 for new U-joints, and balancing) and was installed. Job done.
Right? Well almost....
I took Shelby home Friday and of course drove it cautiously to break in the new rear end gears.
Making sure they got well lubed and established a good pattern so hopefully they wouldn't
"howl". I got it on the road and quickly noticed that about 45 to 50 the car started to shake.
The faster I went the worse it got. By 55 it rumbled and vibrated so bad you thought the
whole rear of the car was going to fall off. I got home finally and called Glen at his shop,
informing him of the new development. The weekend passed and I took it back on Monday.
Glen raised the car up on blocks and ran Shelby in place so the driveline could be observed.
We put a screw driver next to driveline and sure enough a BENT driveshaft. Wap, wap, wap!
Glen called Mesa Driveshatfs informing them of their "fine" job and requesting it be picked up
and redone. A few hours later Glen received a call from Mesa Driveshafts. The caller told
Glen that their driver had just rolled their shop truck near Glen's shop, trying to avoid a dog
in the road (right!). They asked Glen to go check on their driver since he was upside down
in the desert. Glen quickly left the shop to go check on the driver. When he arrived at the
wreck site, paramedics had him sitting on the ground and it appeared he was unhurt just
shook up pretty good. He had rolled the truck 3 times but had his seat belt on. (I later found
out this was the 2nd shop truck he had totaled this year.
Anyway, a day or two passes, the driveshaft gets "Re-balanced" and reinstalled for the 2nd
time. As I write this I am waiting anxiously to find out if that cured the vibration problems!
Stay tuned and I'll let you know.
NOP! That didn't work either. We got the driveshaft back and installed it, even though
it didn't appear to be any different than when we sent it to them. No marks, no NEW
balance weights, straightening marks or torch burns, no New nothing! I tried it and no
change. Still vibrated BAD!
Matter a fact, Mesa Driveshafts outright lied to us telling us they had checked it and that
it was properly balanced. When in fact I just knew they hadn't done a D__M thing to it.
SO. I threw it in the Jeep and drove 45 minutes to "Dick's Drive Shaft, Inc. in Phoenix.
http://www.dicksdriveshaft.com They got me right in and went to work on the shaft.
Now these guys know their stuff. It was also apparent to them that the shaft hadn't been
balanced. It still had the FACTORY riveted weight on it. DA! They took it all apart and
in so doing found that Mesa Driveshaft had used not only the wrong U-joint but had even
put old worn out C clips in to hold on the end caps. They put it on their straightening
lathe and it was evident that Mesa Driveshafts hadn't made any attempt at straightening
it. It was bent in 5 places. They straightened it of course and put NEW U-joints on it.
After determining that Mesa Driveshafts had welded the end Yoke on it OFF center. DA
I can't express enough my thorough DISGUST with Mesa Driveshafts and I truly hope
they enjoy this FREE advertising I am giving them.
"Dick's Drive Shafts did a fine job, quality work and pleasant as well, in about an hour
and I was out of there for $80.00. I drove back to the shop and installed the newly redone
shaft for the third (or 4th) time and took it for a drive. Better.. but still had that annoying
vibration at about 50 mph (but getting better). Now at least I knew (or felt) that the shaft
itself was straight.
Next stop was SPECTRAC Suspension Center http://www.spectrac.com located in
Gilbert, AZ. These guess also know their stuff about suspensions. They checked the
drive-line pinion angle with their gauges and found it to be OFF by about 3 degrees.
So they installed brass 3 degree wedge shims under the rear axle housing pads to change
the pinion angle to where it was supposed to be correct. They also (hand made) and
installed new axle U-Bolts with locking nuts. This was supposed to make everything
just like it is supposed to be and hopefully correct and eliminate my annoying vibration.
$146.23 later! Seriously they did fine work and really tried their best to help me with
the problem.
NOP that didn't do it either! But again, it's getting better. At least now I can drive the
car and have run it up to over 100 mph. But it's still there.
SO, I ordered a new Aluminum driveshaft from Coleman Racing. A great buy at
$256.90 plus shipping of $9.00 to me. Part #16633 -50 1/2 long with 2 new 1310
U-joints already installed on it.
I'm told that an aluminum driveshaft has a tendency to absorb more vibration than
standard steel shafts. So we're going to find out. The new shaft just arrived today
(01/11/03) and come Monday I'm taking it to "Dick's Driveshafts to have the yoke
taken off the old shaft and installed on the new one AND have them put it on their
lathe to check it's balance and straightness. Just to be sure! Hopefully this will finally
cure my vibration problems!
I got the new driveshaft balanced, it's perfect. At the same time, I needed to pull the
transmission to replace the plastic speedometer gear inside the trany with a new one
so my new speedometer would work. When we pulled the trany out of the car we
noticed that the rear transmission mount had oversized bolt holes, which had been
cut by a cutting torch to enlarge them. Evidently a previous owner had difficulties
getting the trany mounting bolts to line up with the bracket, so they just used a torch
to make the holes bigger so the bolts would go in. After replacing the speedometer
gear in the trany and replacing the rear transmission mount. We got it all buttoned
back together. I also replaced the front engine mounts as well since one had a slight
crack in it.
Guess what? The VIBRATION went away! Evidently it was the rear transmission
mount in combination with the bad front engine mounts that was causing the vibration
all along. The new aluminum drive shaft I'm sure probably helped some too but now
that it has no more vibrations, who cares.
Now finally the car runs up nice and smooth to well over 100 mph+! But what a time
consuming and costly problem to try to find.
To see the BEST and most complete article I've ever seen on Ford rear ends GO HERE
Thanks to Kevin kevinstang67@aol.com a fellow VMF'r.