Swap?

[seeyabye]

Are there any differences beyween the 84-5 and the 86-7 transmissions? I just bought a 85 GN with a freshly built transmission and a new 2800 stall. The transmission in my 87 has been doing some mystery shifting and is the original (125k). I was going to swap the two and throw a shift kit into the new one. The trans that is in the 85 is supposed to be out of an 86, but I don't know if that is true. Would this work, or should I just rebuild the transmission out of the 87?

 

[chris718]

the later model carries a larger servo cover and piston coded 694 and 692 and improves 1/2 and 2/3 shift quality over the earlier models.the later also carries a heavier accumular valve spring and revised land diameters on the accumulator valve.shift timing is almost identical but shift feel is firmer with the later models.

 

[seeyabye]

Thanks for the information Chris, do you think the swap is worth the time? Should I Swap convertors and have my transmission rebuilt, or just swap the whole thing and firm up the shifts with the shift kit. Are there any durability differences? Thanks in advance.