Rear end rebuild...

[P72Ford]

and sometimes ring gear bolts (shouldn't need)

You should always replace the ring gear bolts.

I've never had a deluxe kit that didn't include them.

They are in there for a reason.

[johnunit]

What speed are you shifting into 2nd at full throttle? That will give a good idea of rear gear ratio.

Even being a P72, I doubt it's a 3.55.

[1990LTD]

probably a 3.08 or 2.73, granny gears. an easy way to tell is to jack the rear of the car up, put jackstands under the axles and in neutral, put a chalk mark on the driveshaft so you know when it's done 1 complete revolution. have a buddy put a chalk mark on the wheel and one on the car (it wipes off) so he can tell when it's done 1 complete revolution.


if he gets just over 3, it's 3.08.
about a 1/4 under 3? 2.73
3 and a half = 3.55


i think. i'm just making that last bit up based on what i know about gear ratios

[86VickyLX]

You should always replace the ring gear bolts.

I've never had a deluxe kit that didn't include them.

They are in there for a reason.

Why if you're not taking off the ring gear?

[P72Ford]

Right.

Only if you're seperating the original ring gear and differential.

[86VickyLX]

Right.

Only if you're seperating the original ring gear and differential.

ok. Then I could understand replacing the ring gear bolts.

[gadget73]

the ring bolts are just grade 8 right? or are they something special ?

[P72Ford]

I believe they are grade 8. But I also believe the head is bigger than that of a conventional grade 8 bolt of the same size. Like a grade 8 bolt, they have a built in flat bearing surface under the head (all good grade 8s should). However, the larger head of a conventional ring gear bolt means a larger bearing surface, which means less stress under the surface. Grade 8 bolts also have a taller head.

Also, remember to oil the bearing surface when installing the bolts, to get a more accurate torque rating. Or... just use and angular displacement torque method, which is far more accurate than a conventional torque wrench.

[trwp72]

Ok, latest on the rear end in my car... Went to the local tire shop and general car repair shop I use, and the guy pulled the back cover. The fluid was still bright red, and didn't smell burned or otherwise bad. The ring and pinion gears look BRAND NEW. They didn't even have any shiney spots on them where they "mesh"... We put the cover back on, filled it with gear oil, and then ran it on the lift... it is very obvious that it needs bearings, as it is making a very bad growling noise in the center (pinion bearings) and the ends of the axle... The axle bearing I put in last year is even making noise, probably already wore it out due to the other bearings being so loose... The tire place can't do the rear end work, so I went to a few local shops I know... they all wanted $500.00 and up, mostly UP.... A friend of mine put me in touch with the mechanic for the local Yellow Cab company, he does alot of work for him, as he buys and sells old policecars, mostly Crown Vics... Anyway, this guy has been working on the Fords since the early 80's for Yellow... So he says he can do it, and quotes me a price of $120.00! He said he can do it in a few hours... So he is doing it Saturday morning. He is doing it at his house... So for today and tommorow, I am driving back roads to work, instead of the interstate... Don't want the thing coming apart.. as it is LOUD when you get above 55 MPH! OH, I wrote down the numbers from the tag on the rear end, but forgot them at home this morning... I'll post them tonight when I get home...

I think he will start doing alot more work on my car, since he is so reasonable... I think next month I will FINNALLY get the H.O. intake, Plenum, and new throttle body, and a H.O. fuel pump to go with it. I put the new H.O. motor in it... almost two years ago now.. (Damn time flies!) and have never gotten around to installing the intake, etc. since I had to get it powder coated etc... I know--- procrastination!!!

[rick99601]

[Lincolnmania]

damm 120 is cheap.....i get 300, and most shops get 500+

[86VickyLX]

You probably need axles too if your axle bearings are shot.

[trwp72]

I got two of the axle repair bearings in case we need them. I am trying to do this as cheap as possible right now... if it needs axles, I will buy them when my tax refund comes in. I know alot of people baulk at using them, but I had to use them on my 89 Caprice, and had no issues with them. In fact I talked to the guy that bought the car about a month ago, and he said they were still fine, with no rear end noise. (The bearings were put in in 1998) I solde the car in 2000 when I bought this car... Can't wait until tommorow to find out what the condition is, and get the rear end rebuilt!

[trwp72]

Also, here is the rear end tag numbers:

V014E
08 88 OMO3

[P72Ford]

3.08