DIFFERENTIAL SWAP

[blusmith]

DIFFERENTIAL SWAP. '82 Spider man is back on the road aftera rebuld But diff is terribly noisy despite being checked while out of the car , new oil etc . I was told that it was NOT a spideer diff and might have come from a Fiat 131 (!?) Can the experts tell me what diffs are interchangeable with a gen 124 spider set up because I will have to source a second hand here in New Zealand and repair it. Thanks Chris

[divace73]

The 82 had the 131 style of diff ( in fact from around 78 onwards)

[So Cal Mark]

the 131 ratio was different than the Spider

[BEEK]

the 131 diff has different angle on the upper brackets, and drum brakes here in the usa. both issues can be solved, the brackets from a 124 can be welded on, and the drum brakes can be changed for disc, from a 124 too.
i would check the ratio, like mark said

[blusmith]

Thanks everyone - I now know where to start.

[djape1977]

131 'had 3.7, 3.9 and 4.1 ratio depending on the engine size. smaller the engine, shorter the ratio.
diesel and automatic would have had 3.7 or even longer