i have a 73 valient. 225 auto. the rear end has obviously been swaped, because the bolt pattern is 5x4.5" whereas the front pattern is 5x4. what rearend is in my car??

Don't know, but most likely it's a newer 7 1/4. How many cover bolts and what's the diameter of the axle tubes?

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Joshua

10 bolts

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Joshua

looks like i got an 8 1/4. worth upgrading to lower gears/ltd slip?

The best gears depend on a lot of factors not related to the rear end itself. For instance a numerically higher gear is typically used with a 170 than a 225, or with a manual trans rather than an automatic. Limited slip differentials are easy to come by for the 8 1/4.

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Joshua

what vehicles would typically have an 8 1/4 with a ltd slip and gears in the 3:73-4:10 range. and yes i do want gears that low. i dont drive on the highway. also, are all 8.25 rears 27 spline? and are they all c clip style?

Dakota pickups frequently come with 3.55s and some with 3.90s. All '96 and older 8 1/4s are 27 spline and all are C-clip. '97 and newer is 29 spline.

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Joshua

Not all 7-1/4s had 9 bolts. Some I have had with 10 but a slightly different cover. I had one oddball 7-1/4 that had 2-1/2" tubes out of the housing flared to 3" a few inches out from the pumpkin. I got it because it was supposed to be an 8-1/4 but was not; the guy just assumed that because it was a "10 bolt" it was an 8-1/4. I do not have it in front of me as we speak, but I do remember looking thru my '80 factory parts catalog and ther was an up to/after date associated with the 7-1/4 that year; IIRC it was something like3/1/80; cover was different P/n, housing was different p/n; could this have been when the7-1/4 went from the 8-3/4 type of axle bearing to a C clip? I believe that everything but gear packages and carrier were different between them.
Oh and Dakota rear ends? They were availble with 7-1/4 at least thru/including '90. (that was what used to be in my '90) I put an 8-1/4 in there when the side gears cracked and cracked the carrier housing. 87-90 had 5 on 4-1/2; 91-up had 6 lug. Somewhere after 90 they switched yokes to accept a larger U joint. When I did the rear end swap, the truck I got the 8-1/4 out of, had been in an accident, the housing was actually bent! That was the only Dakota he had in at the time so i wound up getting another rear end from another yard. This one was out of like a 94 and I wound up using the axles out of the bent '90 housing and the yoke too, and slapped the 6 lug axles and '94 yoke on the bent '90 housing when I took it back for a refund which I OK'd with the initial JY owner before I "built my own" between the 2 rears to get the truck back running again. that was after my anti-maintenance, run-it-in-the-ground brother in law wound up with the truck.... nother story

"I had one oddball 7-1/4 that had 2-1/2" tubes out of the housing flared to 3" a few inches out from the pumpkin. I got it because it was supposed to be an 8-1/4 but was not; the guy just assumed that because it was a "10 bolt" it was an 8-1/4." by VolareDon

Yeah, that's the 7 1/4 diff that looks like an 8 1/4. I've seen those in a lot of Diplomats, Gran Furies, 5th Avenues, etc.

The 8 1/4 differential in my '78 Volare came from an '82 Diplomat cop car.

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

I have a 1966 Belv.II slant 6-3 speed column shift came from the factory with a 3.55-1,7-1/4 With 4-1/2 bolt patern Should be a good swap into a late dart or duster?

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YOU SNOOZE YOU LOSE

i want to change the bolt pattern on the rear end to the small pattern. whats the best way to do this myself. i was thinking if i got a small pattern drum, i could take the axle out, knock out the studs, then put the drum on the axle, center punch the stud holes. then drill away. any thoughts??

I'd sure think about swapping in front disks with the 4.5" bolt pattern, instead of trying to change the rear to 5-on-4".

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"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO

but i already have the wheels 14x7 mags in 5x4" and i dont want to invest a lot of money into this car. for disc swap id need spindles/rotors/mastercylinder and mabye more stuff.
to get my wheels to fit i just need to figure out how to accuratly drill the stud holes.

bring the boom; Sell or trade the wheels for 5 on 4-1/2s, you will have less trouble finding a replacement should you accidentally damage a rim! As 5 on 4 ismuch less common you MIGHT just find, that you come out a bit ahead on the deal as more common uaually=cheaper to buy in the same style of rim.

onelight; a 7-1/4 in a Belvedere? I never knew that B bodies got that weakling rear end. Unless its a Sure grip version I wouldn't run it; Now if it was an 8-3/4? '66-70 B bodies are the ones that F body (aspen/Volare) guys are after to do their rear axle swaps. I believe it would be too wide for an A body though, w/o the "stinkbug" look of the rear wheels sticking out too far. The only way around that would be non-stock, offset wheels.