I know just like the 305 build not everyone is going to approve of what I'm doing and some will feel it's completely sacrilegious and that's ok, everyone likes what they like and are free to state their opinion and do what they like on their own car.

I enjoy building things, the planning , the measuring, the welding, the fabricating. I enjoy that part of the hobby more than anything. The more I looked at the moser 12 bolt, the s60, or 9" from any manufacturer it just didn't excite me because I was going to spend $3500 to $5000 on just a rearend that doesn't add to the fun factor and I would be done installing in 1 day more than likely. Not much fun in my opinion. I'm not very hard on my car but I do have the occasional fun moment and with the engine I'm building (if the machine shop ever gets finished) I was a little worried about the 10 bolt behind a manual transmission and don't want to take a chance with breaking something and it's something else to mess with.

The rearend I decided to go with is from a 1997 Mercury Grand Marquis same as the crown vic. I got a lot of info from 2 other guys I found that have done the swap on other forums, The upper cast ears are dead on the gbody height from center line, the ears are spaced out a little over an inch more then the gbody. For our cars the downfall of the mustang 8.8 was the poor position of the ears even though lots of people use them in g body's, with the crown vic it addresses that issue. Here is some pictures I took of the crown vic rear end vs the 8.8 mustang rear that people use. The pinion offset is roughly .500 to the passenger side on the 7.5 and CV 8.8. The CV 8.8 has 3" tubes.





Here's some pictures borrowed from other discussions that aren't mine.

Here is the rearend housing as of now after spending $80 on it at Pull a Part, $50 to have it sandblasted, and some time with a grinder (while grinding brackets off i did remove the other emblem from the housing). In this picture I have the upr g body spherical joints in the housing test fitting them.

I know you're happy to have made a decision and able to get to work on it. It'll be strong enough and save you a lot of money. I don't see it being any more sacrilegious than putting in a 9", like so many of us have done over the years. Looking forward to the build.

The 8.8 is also more efficient than the 9 inch which is almost a worm drive. The police versions of the 8.8 have lower gear ratio options plus impact shields. 3.27 is the standard gear ratio for CVPIs with a optional 3.55 ratio. In 1998 Ford Panthers switched from triangulated 4 link to parallel 4 link so you want to avoid post 1997 models. 1997 was also the last year for the Aero generation of Ford Panthers, 1998 was the first year of the iconic Whale generation Panthers. This means for donors you want to avoid the common Whale Panthers and look for the older and increasingly rarer Aero Panthers.

So the above picture is where I'm at at the moment which is the very far along. As far as measuring everything I did jack the car up, removed the wheels and tires, undid lower control arms to get pinion at 0 degrees , everything level, and plotted the rearend points on the floor with a plumb bob. I was mainly concerned about width, axle centerline, and the lower control arm location but also ploted pinion center. It was all just to get rough ideas. Below is driverside axle flange, control arm mounting points, shock/coilover mounting point, axle centerline, and pinion centerline. Not the greatest picture. Center to center the lower links are 44" apart, pinion is .500" to passenger side from center, and with drum brakes wheel mount to wheel mount was 57 13/16".

First focus is getting the housing in order which is lower control/trailing arm brackets, housing ends, and spring perches. This is what I'm using.

Lower control arm brackets
https://www.medievalchassis.com/product/brackets-trailing-arm-multi-hole/

Housing ends
https://www.strangeengineering.net/product/small-gm-weld-on-housing-ends-for-3-150-bearing-pr.html/

Spring perches
https://southsidemachineperformance.com/shop-1/ols/products/weld-on-coil-spring-pads

Interesting thing is that none of the 3 major rearend manufacturers will sell you any brackets. 2 years ago they all sold brackets. When I ask why it was explained that if the can't weld it on themselves they want no liability. I had to order the above from a roundy round race car shop. I needed the 10° angle brackets like stock to line up with lower control arms. If these won't work I'll just build my own we shall see.

Housing ends are Strange 1143 , they use the Ford 3.150 bearing with a gm bolt pattern as I'm using ls1 rear disc. You could also use moser 7900fm but they only use a ball bearing. I wanted to run a tapered bearing. One other thing is the 3 different people I talked to at Strange were helpful and answered all my questions and helped me. Moser not so much.

Spring perches are from southside machine. I'm going with my coilovers but I wanted spring perches also so I have the option.

Looking forward to seeing this one. I'm curious, what's the possibility of using the Crown Vic as-is? i.e., I know wheel studs would be wrong, how about axle width? Have to be narrowed/stretched (hard to tell form the pictures)? Spring perches seem close, not close enough? I know you will do it right, I'm just curious how wrong it would be for the 80/20 crowd like myself

I've always thought the 8.8 in some form would be my upgrade path when I can get back on the Monte, but I was leaning toward the Explorer with two "short" axles and a truss kit (either from Southside or fabricated from scrap plate, depending). This is the first I've heard of the Crown Vic as a donor, the Mustang always seemed like a hack fix with the adapters, which honestly seemed like way too much money for a bandaid fix that still needed upgrades (5 lug, axle upgrades, etc) to be a significant gain form what I heard.

The short of it is I think it would work with just shortening it and upper control arms, the above picture of the gbody and crown vic rear end the CV housing had already been shortened. I will get into more of simalarities and differences as I move along. I will say that the car i pulled the housing from had a sweet disc brake setup with the ebrake in the hat.

The main 2 threads I got the info from have quite a bit of detail and are good resources. The first is Tokarz1 Midlife Crisis build thread, great build going on, lots of pictures with this rearend and frame only. Here is where the comparing axles start.

Post in thread 'Midlife Crisis Monte Carlo Build' https://gbodyforum.com/threads/midlife-crisis-monte-carlo-build.76980/post-762348

The second one I followed was 78Maliburacer here is his thread.

https://maliburacing.com/forum/threads/crown-vic-8-8-rear-installation-is-a-success.127603/

Once again tokarz1 thread has tons of comparison info between the 2 rearends.

Here is another link of a guy that used everything stock including upper and lowers and just narrowed it.

Probably won't be much progress til next Sunday or so, im still gathering stuff and we are coming out of an outage at work with some long hours. I was off today so I went and refilled my acetylene bottle for my pre and post heat on the cast center when I weld the tubes to it and picked up some 3/32" 309L tig rod. I thought I had some but I didn't so I just got 1lb which was $8. I'm not a very good welder or metalurigist but my welding instructor made us weld dissimilar metals and 309l will fit the bill for this while letting it cool slowly.

A co worker had a 1.25" bar and 3.150" pucks from building a 9" so thankfully he let me borrow it so that saved some money. The 8.8 has 3.062" carrier bearings but I was able to get them off ebay for $50 and I picked up a pinion centerline jig for $23. This should be the only tools I need for this project hopefully. I did check the straightness of the housing and it's out a little but if I weld the tubes to the center in the right order I should be able to pull it straight.

I have everything to start work on the housing. Below is the lower control arm brackets from Medieval Chassis and the spring perches from SSM. I'm using my Aldan coilovers but wanted the option to put springs on if I wanted in the future.



I also recieved the Strange 1143 housing ends, A1013 bearing set (timken set 20), b1300hstkit t bolts, and b1105d spacer for ls1 rear brakes.

Last night I fit everything together with the 98-02 ls1 rear disc brake backing to come up with a measurement. All of the measurements are on the web but I would rather measure myself. Here is the setup.


After measuring this is what I came up with to get the stock width.

I'm wanting to keep my car drivable while I do all this but I want to remove the 7.625 10 bolt so I can mock up the new rearend and get brackets on this Sunday. I plotted out the old rearend mounting points by dropping the driveshaft and lower control arms, getting the pinion to 0 degrees, rearend level side to side, and using the plumb bob to mark points on the floor. I feel that I could build the new rearend off those points but would feel better getting it in place, bolting brackets to control arms and swinging them up and tacking that way I know it fits. This is how I did the 3 link on my truck in 2015 and it worked well.

Is there enough slack at the pinion brakeline to drop the old rearend and get it kind of out of the way or should I just disconnect and clamp brakeline and re bleed the rear brakes so I can remove the rear all the way? I hate bleeding brakes lol.

That pinion flex brake line is pretty short...and can sometimes destroy the hard line fitting when removing. Your car is pretty clean though so that shouldn't be an issue. Pretty sure you'll have to remove it from the axle to move the axle out of the way though.

Smart thinking welding the axle brackets on with the arms in place, it's worth the rebleed...

Lance, thank you for the info that's what I was looking for. I was hoping someone that was recently familiar with that area of the car would answer. I'll just remove the rearend completely and rebleed.

Completely different application but when I did the truck I found the wheel base I wanted and transferred the mark to the frame. I put a long 3" u bolt around the axle lifted it where I wanted and tack welded the u bolts to the frame that way the axle could still rotate to set pinion angle and move side to side to fine tune, then just swung brackets up and tacked them. Removed axle then finished welding. The frame was notched afterwards. I daily drove the truck til 2020 sold it and now it lives its life as a full time show truck being hauled in an enclosed trailer in West Virginia as pictured below.

I was proud of that truck, all the shops wanted 10k plus and atleast a 1 year or more wait. The most I had ever done was put drop spindles on a truck but I had a small welder and knew how to use it. I borrowed a car from a relative and used a tiny 1 car garage at my dad's rental house and in 42 days was done with front and rear suspension. Also did all the sheetmetal work to tub and close in bed and built sheetmetal inner fenders for the front. It was a fun project and started me on the "I can do this path". The side note too this is that I had wasted the previous 10 years of my life being nothing but a full blown alcoholic and doing nothing but trying to survive and drink. This project is what filled that idle time and got me out of the devils workshop and I've not drank since and hope I never do. It was no life too live.

Sorry to blab on, Back to the rearend build.

Setting up the rearend


Truck and Monte


The truck living it's retirement life in West Virginia with its enclosed trailer behind it.

I want to add something too this also, one of the guys I followed on his build had quick performance shorten, put gm ends with big bearing on, spring perches, and lower control arm brackets on a 8.8. For around $500 to $600 total you do have that option if interested. Quick performance doesn't charge much it's just a large part of the $500-$600 is shipping housing back and forth.

So I've talked about the lower control arm mounts and what I'm doing there but haven't brought up the uppers. The ears are the same height but they are a little wider and a little farther forward. The g body factory upper arms are 11" and after reasearch of others you can't get your pinion angle right even with the adjustable upper control arms. It seems like the 68-72 a body uppers are the ticket, the factory arms are 10.25". I ordered and just recieved the spohn 68-72 a body uppers with the roto joint in them which is in the first picture. The other pictures are from tokarz1 build just to show the alignment of the a body uppers and the crown vic 8.8.

That truck looks phenomenal and the uppers look like they're going to work out nicely.

Thank you Kevin!

Another detail to this 8.8 rearend is the size of upper ear bushings, they are roughly 2.070" o.d. with an I.d. for a 14mm bolt, g body is roughly 1.850" o.d. with an i.d. for a 12 mm bolt. The 68-72 a body spohn uppers use 1/2" (12.7mm) bolts. So I have 2 options.

-Use the 8.8 rubber bushing with a 12.5mm id to 14mm o.d. spacer I made for the thru bolt.

-Use the g body spherical bushing with the spacers I spent a lot of time machining to get the perfect fit so everything was tight and upper bushing or spacer could not spin in the housing.

You could also drill out the upper arms to accept a 14mm bolt but didn't want to do that so I could have both options now and in the future. Since my car is just a cruiser I'm leaning towards the 8.8 rubber bushing going in, I worry about the spherical bushing and the nvh. The other end of the arms have the roto joint.

I'm a big fan of sacrificing very little NVH gain when using a Delrin Spherical bushing instead of rubber, definitely way before doing poly. Every joint of the 16 in my car is Delrin or a Del-sphere and I think you wouldn't mind the improvements.

Didn't realize the 8.8 rear bushing has a bigger OD than the GM counterparts. When i first installed the 8.5 the Camaro 1LE rubber bushing were installed in the rear. Later went to the Delrin HR in the rear location. Did some homework, 7.5 and 8.5 can use the same bushing, and the 12 bolt from what i saw on Ridetech use the same R joint, all are 1.85" OD. ".
https://www.ridetech.com/product/19...m-r-joint-bushing-and-tool-kit_11227299/

Was wondering if anyone make a Spherical for that 8.8 bushing.
Looked at Global West and they show a Spherical for the 8.8 Mustang. Rather on the price side.
https://www.globalwest.net/mustang-...rear-ends-with-performance-bearings.html

My concern about using rubber at that location is the alignment of the arm is somewhat compromised being it's not in direct alignmnet. A rubber bushing is always stress more, like side loaded. A spherical joint on both ends of the UCA would make that pretty much a moot issue.

I tried shopping Rock for an UCA rear bushing and couldn't find a part number. What Vic year does the rear fit?
Bob

Up until 1997 was the Aero generation of Crown Vics used triangulated 4 link suspensions similar to G bodies. In 1998 the Whale generation of Crown Vis debut which were redesigned with parallel 4 link rear suspensions with a Watts linkage which has major differences with G bodies.

Picture of a post 1998 Crown Vic 8.8 that you want to avoid.

Bob,

1997 crown vic bushing 2.070 o.d./ 14 mm bolt i.d.
G body bushing 1.850 o.d./ 12 mm bolt i.d.
Mustang bushing 1.850 o.d./12 mm bolt i.d.

Maybe i wasnt clear but as pictured above I have brand new raybestos 570-1033 rubber bushings ($24) that are made for the 1997 crown vic 8.8 rear end (2.070 od/14 mm bolt id) sitting on my bench. I made a spacer that fits inside that makes the I.d. for a 12 mm bolt like the g body.

Also on my bench is the UPR Teflon lined spherical bushing for a g body as pictured above. It is 1.845 o.d. and i.d. for a 12mm bolt. I made a steel bushings on a friend's lathe that has to be lightly driven into the housing ear and then the upr spherical bushing can be lightly driven into it then the nut on the spherical bushing gets a little blue loctite and tightened and fits like it's in a g body, the spacer is laying behind it in the above picture.

Sitting under the bench as picture above is Spohn A-body arms with a Del-sphere pivot joint.

I have both options in front of me and can swap out as I please.

The nvh thing is subjective, you say very little nvh others say its a lot of nvh. I think we need to remember what I use my car for. Me and my wife drive my car to carshows, cruise ins and to get ice cream on Sunday evenings and occasionally i leave a few black marks so anymore nvh is not worth it to me. If it wasn't for the new engine coming the 7.5 10 bolt would stay back there with the factory rubber bushings and factory floppy control arms. If you drive the factory bushing in a 1/4" farther the alignment is perfect as pictured in tokarz1 build below. As always I do appreciate your opinion Bob.

Bob, what's your or anyone elses thoughts as far as delrin lined spherical joint vs the Teflon lined that I pictured above. The reason I chose the upr spherical Teflon lined is because of the ability to tighten down with the large nut and the nut and outer edge lip is 2.235" where the hole for the upper ear is roughly 2.074". Even though every thing is a tight fit I wanted the nut there to help. I assume the upr Teflon is more a racing application and will have more nvh than the umi or spohn delrin just because of design.

I can't speak to the difference between Delrin lined and Teflon lined joints as I went straight from rubber bushings to all Delrin lined bushings. I can however speak to what adding just one control arm with straight rods ends does to NVH, it increases it exponentially... Took the wife to a cruise in yesterday and she asked several times "What is all that noise from?"

I know a lot of people with real nice PT cars with all Delrin bushings and they are completely happy. My "guess" would be the Teflon lined would be a bit more compliant than Delrin but I don't really know.