rear

[premo]

both, the one wheel peel is embarassing and the rear that is in there now has stock gears

Are you going more for the posi or just the gear change?

 

[premo]

i was planning on goin with a monte rear, until i was told they were a diiferent width and there wld be fabrication... thats when i started to consider just rebuilding mine

i used a rear from an 87 Monte SS. Got posi and 3.73 gears. Thae swap is very easy and the rears can be had for around $200.

I got a rear from an 86 SS with the 3.73s for $100!

 

[-83MONTESS-]

i was planning on goin with a monte rear, until i was told they were a diiferent width and there wld be fabrication... thats when i started to consider just rebuilding mine

i used a rear from an 87 Monte SS. Got posi and 3.73 gears. Thae swap is very easy and the rears can be had for around $200.

I got a rear from an 86 SS with the 3.73s for $100!

I was always told that all the gbodys were the same width wise. Thats why there all a direct bolt in. I dont believe the monte rear is wider or else it wouldnt be considered an interchange.

 

[81Regal]

i was planning on goin with a monte rear, until i was told they were a diiferent width and there wld be fabrication... thats when i started to consider just rebuilding mine.

Whoever told you that was full of chit, All stock G body rear axles are the same width, doen't matter if it came from a Cutlass, Regal, Monte, El Camino. No fabrication needed. If you wanted to put in a 9" or 12 bolt there would be some fabrication needed.

 

[premo]

thats what i thought, i even used monte frame rails to replace my rotted rails... so a 10 bolt will fit right in?

i was planning on goin with a monte rear, until i was told they were a diiferent width and there wld be fabrication... thats when i started to consider just rebuilding mine.

Whoever told you that was full of chit, All stock G body rear axles are the same width, doen't matter if it came from a Cutlass, Regal, Monte, El Camino. No fabrication needed. If you wanted to put in a 9" or 12 bolt there would be some fabrication needed.

 

[AlanB]

Premo86,

A Monte rear from 1978-1988 will fit your 86 Regal.

Aside from the GNX, there were two different rear end housings installed by GM in the G-bodies, the 7.5 housing (which includes the 7.625) and the 8.5 housing. The 8.5 rear was installed from the factory in the following cars:

85-87 442s (3.73)
84 Hurst/Olds (3.73)
84-87 Turbo Regals (3.42) includes Grand Nationals, T-Types, WE4, etc. If it had a factory turbo, it had an 8.5.

All other A/G bodies from 1978-1988 came with a 7.5 housing. The 7.5 housings are completely interchangeable between Montes, Cutlasses, Regals, Grand Prix, Malibu, all of them. Same suspension mounting points, same brakes, same driveshaft length, same width. The more desirable rears in this category are the 85-88 Monte Carlo SS rears which came with a 7.625 ring gear and 3.73 ratio. Other than the size of the ring gear, the 7.5 and 7.625 rears are the same and the housings are completely interchangeable. I suppose the 7.625 is a wee bit stronger.

The 8.5 rear requires a shorter driveshaft than the 7.5 rear. If you pick up a 8.5 rear, you should try to get the driveshaft from the same donor car, otherwise you will have to get your 7.5 shaft shortened by about an inch.

When looking for a performance gear ratio in a 7.5, your options are typically limited to the higher performance models:
83-84 Monte Carlo SS (3.42)
83 Hurst/Olds (3.73 I think)
85-88 Monte Carlo SS (3.73, 7.625 ring gear)

The 85-88 Monte SS rears are by far the most plentiful, come with the 7.625 gears, and are the most popular budget swap. I had one in my Cutlass and it served me well. I did eventually break it by shearing teeth off the pinion gear. So much for the 7.625 advantage.

One last thing to remember is that a Posi, or limited slip, was an option on everything, even the 8.5 rears. There are lots of Monte SSs and Grand Nationals out there with non-posi rears. So you should never assume that any rear, even the performance ones, come with posi. You need to check to be sure.

 

[premo]

thank you, that was very helpful

Premo86,

A Monte rear from 1978-1988 will fit your 86 Regal.

Aside from the GNX, there were two different rear end housings installed by GM in the G-bodies, the 7.5 housing (which includes the 7.625) and the 8.5 housing. The 8.5 rear was installed from the factory in the following cars:

85-87 442s (3.73)
84 Hurst/Olds (3.73)
84-87 Turbo Regals (3.42) includes Grand Nationals, T-Types, WE4, etc. If it had a factory turbo, it had an 8.5.

All other A/G bodies from 1978-1988 came with a 7.5 housing. The 7.5 housings are completely interchangeable between Montes, Cutlasses, Regals, Grand Prix, Malibu, all of them. Same suspension mounting points, same brakes, same driveshaft length, same width. The more desirable rears in this category are the 85-88 Monte Carlo SS rears which came with a 7.625 ring gear and 3.73 ratio. Other than the size of the ring gear, the 7.5 and 7.625 rears are the same and the housings are completely interchangeable. I suppose the 7.625 is a wee bit stronger.

The 8.5 rear requires a shorter driveshaft than the 7.5 rear. If you pick up a 8.5 rear, you should try to get the driveshaft from the same donor car, otherwise you will have to get your 7.5 shaft shortened by about an inch.

When looking for a performance gear ratio in a 7.5, your options are typically limited to the higher performance models:
83-84 Monte Carlo SS (3.42)
83 Hurst/Olds (3.73 I think)
85-88 Monte Carlo SS (3.73, 7.625 ring gear)

The 85-88 Monte SS rears are by far the most plentiful, come with the 7.625 gears, and are the most popular budget swap. I had one in my Cutlass and it served me well. I did eventually break it by shearing teeth off the pinion gear. So much for the 7.625 advantage.

One last thing to remember is that a Posi, or limited slip, was an option on everything, even the 8.5 rears. There are lots of Monte SSs and Grand Nationals out there with non-posi rears. So you should never assume that any rear, even the performance ones, come with posi. You need to check to be sure.

 

[-83MONTESS-]

Premo86,
All other A/G bodies from 1978-1988 came with a 7.5 housing. The 7.5 housings are completely interchangeable between Montes, Cutlasses, Regals, Grand Prix, Malibu, all of them. Same suspension mounting points, same brakes, same driveshaft length, same width. The more desirable rears in this category are the 85-88 Monte Carlo SS rears which came with a 7.625 ring gear and 3.73 ratio. Other than the size of the ring gear, the 7.5 and 7.625 rears are the same and the housings are completely interchangeable. I suppose the 7.625 is a wee bit stronger.

The 8.5 rear requires a shorter driveshaft than the 7.5 rear. If you pick up a 8.5 rear, you should try to get the driveshaft from the same donor car, otherwise you will have to get your 7.5 shaft shortened by about an inch.

Thanks for clearing that up. I didnt know whether or not a 7.625" is different length wise to a 7.5".