Getting 3.73's Installed...

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Wheel bearings and seals, check the brakes/wheel cylinders, synthetic gear lube and friction modifier.
If you can spring for it an aluminum drive shaft or at least new u joints and drive shaft balance.
Oh, and an extra set of rear tires, have fun
 
The T-loc shouldn't be ignored. A high mile differential will have dead clutches. Nothing will be more of a pi sser than re-assembling the rear end w/ new bearings, only to ignore the T-loc and have one tire blazing away during a burnout.
(That would be me, speaking from personal experience, as recently as this last build)
75.00 extra that should've been spent on the dead diff while it was out right in front of me. And now that's one more thing that'll have to get dealt with after the fact.

And laying on your back under the car wrestling the ring gear out While all of that sticky, gooey, stinky 90wt gear oil is running back down your forearms is such fun.
 
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The T-loc shouldn't be ignored. A high mile differential will have dead clutches. Nothing will be more of a pi sser than re-assembling the rear end w/ new bearings, only to ignore the T-loc and have one tire blazing away during a burnout.
(That would be me, speaking from personal experience, as recently as this last build)
75.00 extra that should've been spent on the dead diff while it was out right in front of me. And now that's one more thing that'll have to get dealt with after the fact.

And laying on your back under the car wrestling the ring gear out While all of that sticky, gooey, stinky 90wt gear oil is running back down your forearms is such fun.

Car has 60k on it. As of now, there will be no blazing burnouts lol. I baby her. And I will not be doing the work. All that being said.. Should i still have the t-loc serviced?
 
Wheel bearings and seals, check the brakes/wheel cylinders, synthetic gear lube and friction modifier.
If you can spring for it an aluminum drive shaft or at least new u joints and drive shaft balance.
Oh, and an extra set of rear tires, have fun

I was looking at the aluminum driveshaft. Do you think that it's worth it?
 
I was looking at the aluminum driveshaft. Do you think that it's worth it?
If you just baby the car it's not. Especially with 60k on your original. I'd probably look at some u joints and call it good. The aluminum piece is stronger,lighter(less of a power reduction),etc but for a nice day driver-overkill. Imo
 
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Sorry should have asked for more info, just change the u joints, I would have the shaft balanced, 60k mile nice day driver why 373s? If it's an auto ok
If its a stick I'd do 355s
Whats your reason for the gear change?
Don't get me wrong, great mod but 373s raise your rpms on the highway, lower gas mileage. JMO
 
Sorry should have asked for more info, just change the u joints, I would have the shaft balanced, 60k mile nice day driver why 373s? If it's an auto ok
If its a stick I'd do 355s
Whats your reason for the gear change?
Don't get me wrong, great mod but 373s raise your rpms on the highway, lower gas mileage. JMO

All stock, 5 speed. But I'd like to do some cost effective upgrades to help with performance. 2 of the top 3 I always read are gears and subframe connectors. Had the connectors done already.

Just trying get an idea for budget purposes. Unfortunately I'm not very mechanically inclined so I'll paying for labor for everything. I already have a leaking oil pan gasket and rear main seal to get fixed. Which I assume will be costly.
 
Buy a repair book, there are a lot of things even marginal mechanics can do to save money.
Right about the sub frame and the gears, although I would suggest going with 355s but it's your call.
Don't forget the brakes, they are good enough for driving around town but are marginal for spirited driving, there are better stuff out there that will let you keep the four lugs and haul it down from speed better than stock.
Once you get a little grease under you nails and tell someone you did the work you'll get it.
 
Not mechanically inclined.......:nonono:

You're starting into the modification bug. A year from now you'll be doing things to your car that you wouldn't believe you would ever have done.

Change out the clutch discs in your rear end. You'll wish you did otherwise. Our cars are to old, babied or not. The old clutches are going to start falling apart. It's not some magic to do these things, just read up on the subject. There must be a thousand youtube videos of people doing this exact thing.

Look at the positive side, you'll get some new tools! Plus you'll be proud of yourself when you do the repair.

I agree with karthief, 3.55's would be great. 3.73's aren't a bad choice, just a little annoying on a longer highway type drive.
 
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And you will drive it long distance someday, and then more often, and farther, thinking well Detroit's not that far the Woodward dream cruise would be cool, mustang week, and suddenly your in Vagas living in that mustang because you lost at blackjack and your wife divorced ya and, wait, sorry, got a little off this morning.
Point is once you get started down this mechanical mayhem some call mustang life, very few return to stock life.
So put some wax on that hood, there's a bird just waiting to spot ya.
 
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If you are trying to say that upgrades are addicting then I definitely agree! 5 years ago, I'd be doing every upgrade possible! Family life has now given me serious time and some financial constraints!

I do have all the Haynes repair manuals and such but time is the major issue with trying to do the work myself. I've already done all the tune up stuff (plugs, wires, cap and rotor, ignition coil). I still need to change out the fuel filter and change the pcv valve. I had a hard time getting access to the pcv valve screen. So I gotta try to tackle that again.

As of now, I believe I have a oil pan gasket leak which I will most likely try to change out myself and a rear main seal leak which I was hoping to wait until I get the clutch replaced before I touch that. Is there a problem with that?!

I will keep it mainly stock. It's only driven during summer and I hope to pass it down to my boys.But as it is now, it is slow as heck! So I'd like to give it a little more pep.

What are the pros and cons of 3.55 vs 3.73s?
 
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If you are trying to say that upgrades are addicting then I definitely agree! 5 years ago, I'd be doing every upgrade possible! Family life has now given me serious time and some financial constraints!

I do have all the Haynes repair manuals and such but time is the major issue with trying to do the work myself. I've already done all the tune up stuff (plugs, wires, cap and rotor, ignition coil). I still need to change out the fuel filter and change the pcv valve. I had a hard time getting access to the pcv valve screen. So I gotta try to tackle that again.

As of now, I believe I have a oil pan gasket leak which I will most likely try to change out myself and a rear main seal leak which I was hoping to wait until I get the clutch replaced before I touch that. Is there a problem with that?!

I will keep it mainly stock. It's only driven during summer and I hope to pass it down to my boys.But as it is now, it is slow as heck! So I'd like to give it a little more pep.

What are the pros and cons cons of 3.55 vs 3.73s?
Clutch out is a perfect time to take care of the rear main seal.

Pros and cons. With 3.73's, first gear will seem useless almost. with 3.55's it will seem useless almost:D

If you like running through the gears fairly fast because of the enjoyment of it, then either is fine. 3.55's will just allow,the engine to spin a little slower at highway speeds. Little less drone from your exhaust (depending on the exhaust, of course).

Will you want to do much running at the dragstrip? If so, then you might even consider going a little higher numerically, like 4.10's.

Manual wise, the thing to do is go on ebay and look for a set of ford service manuals. I have a set for both my '83 and my '86. There's so much more detail there. I averaged right about $60 for each of them. Great resource.
 
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You might wanna start thinking about a good shifter too, Pro-5.0, Steeda Tri-Ax, etc. Because you will be doing twice as much shifting.

Than being said.. I'm running FRPP 3.73s in my 86 GT 5spd and I love every minute of it, makes me smile every time.
 
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3.55's vs 3.73's debate is really splitting hairs imo. It's a very minimal difference at highway speeds(200rpms) and 1st gear usuage is darn near the same. I have had both and really like both gear sets. My present car I switched from 3.55 to 3.73 and the car performs better(but I have a cam etc and needed more gear). 55's are probably a better choice for a "nice day cruiser" and 73's if you want to maximize straight line performance. The op will probably like either.
 
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You might wanna start thinking about a good shifter too, Pro-5.0, Steeda Tri-Ax, etc. Because you will be doing twice as much shifting.

Than being said.. I'm running FRPP 3.73s in my 86 GT 5spd and I love every minute of it, makes me smile every time.

I picked up a mgw! And I after some of the comments, I was probably going to end up 3.55s.. But then I read the last sentence in your comment! I guess 3.73's it is!
 
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