I have an 84 toyota extra cab with a 22ret and dual cases was wheeling this weekend and came to a stop to shift back to 2hi and rear case wasnt as easy as normal and made a clunk sound when it engaged back into 2hi. Well now there seems to be a vibration/ clunking noise coming from the cases. only seems to do it at low speeds and especially when going up hills. Anybody have ideas on things to check?