D100 pull my Duster?

My truck is pretty much a twin to the OP's. 82 D150, slant and 833OD. I agree with what others have posted, when pulling a loaded trailer getting going is a clutch-slipping affair. Once moving, it does "OK" in 2nd and 3rd. I wouldn't try it in OD unless on the flats or going downhill. My slant is moderately upgraded but no kind of a beast. For as little as I'm likely to need to pull a fully loaded trailer I can live with its lack of muscle - besides, it's otherwise a hoot to drive.