1994 Other Isuzu Models 4X4 Engage

check the front yoke (driveshaft) grease it up it should a grease fitting on the shaft and one on either end to grease the universal joints you can also take it off to make sure it slides smoothly. if you remove make sure you mark the fit relationship so that you put it back exactly as it can off.

[quote:54611e9eef="selvy"]Other Category problem
1994 Other Isuzu Models 4 cyl Four Wheel Drive Manual 125000 miles
----------------------------------------------------------------
I have a 1994 Isuzu Amigo with four wheel drive. How do I properly engage the system? Everytime I try to engage 4 wheel high when it hits about 30 mph a shuddering begins and gets worse if I go faster. I really like my truck and don't want to damage it![/quote:54611e9eef]

are you going that fast in 4 wheel drive on pavement? if so, it's not designed to do that... so stop..... it is only to be used off the pavement.... although, your bearings could be shot in the front wheels, or something is out of balance, like the front driveshaft.