what kinds of things would happen if a three speed auto (3.7:1) was hooked to a 3.9:1 rear?

 

see, the rear on my dads loyale automatic is a 3.9 and maybe the slipping in first and shuddering when when shifting into second is from damage or stress caused by having the wrong rear end on it?

 

I am going out on a limb here, it's prob just worn out.

 

-AK

The Loyale auto's did come with 3.90 rear diffs. I think they did it to try and give them some pep. So, to answer your question, the trans is probably worn out.

 

Sorry.

Running with mismatched final drives would do absolutely nothing when in 2WD, it'd feel exactly the same as if they were right. In 4WD on the other hand... going from a stop it would just lock up, engaging it on the fly could possibly rip the tranny apart.