Best fielded to your local dealer. But imho no it will not void a warranty. They would have to prove it was the cause to the failure. Im not sure what the trans designation is but in the case of a 4r70w the 4 is the # of gears, r is the direction of the output -rear, 70 represents the tow rating -gross weight of the loaded car plus an extra 70%, and w is for wide gear spacing most trans say e for electronic control.
2008 Vista Blue SES Coupe 5spd FRPP Zx3B Suspension
5000K D2S Retrofit
130,000+ miles and still on factory brakes and clutch!
Rep Points dont add themselves