So I have a 1991 E350 RV 460 fuel injected C6 with overdrive don't know the gears in the rear end but I built it to pull my fifth wheel flatbed that was formerly a camper trailer and I'm trying to figure out since both of them lost weight and they're technically a quarter of the weight they used to be if I need to use OverDrive or not because the truck weighs 6700 lb and the trailer only weighs 3500 lb do I treat it like a regular pickup truck a 3/4 ton or do I got to do some fancy shenanigans thank you in advance

 

A C6 is a 3 speed and doesn't have overdrive. I owned an 87 Ford E350 Class C and it had 4.10 gears. I doubt they changed it before getting rid of the 460.

 

OBS460 you might be right but I have an overdrive switch in my 91 and let me tell you it makes a difference since I've been clocked at freaking 115 driving that damn thing but 91 was the last body style of the dent side bullnose like this then it switched to the newer body style with the fuel injection system they added the C6 overdrive for a short period before they got rid of the c6s I've built too many trucks at 33 years of age while being homeless to know what I have and I don't have I just don't know how to use it

This is a carbureted 460 with a standard C6 in a 1986 that I built for under $100 out of scrap metal and lived out of for 3 years this I know has no overdrive but has the same transmission as my '91 as a matter of fact this trailer in the picture is my 29 foot fifth wheel flatbed as of now 😂

 

If you have an OD it's an E4OD. There is no such thing as an OD C6.

If I read your first post correctly the question is should you use OD when towing. With the E4OD yes, use OD. Lock it out if you are in hills and it hunts. Otherwise, leave it in OD.

 

ITs casted on housing just like my 86 once I heal from my fractured hip I'll take pictures but don't expect them until about spring don't get me wrong I may be wrong

 

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