Nissan repair

We have a Nissan Pickup that anytime (in every gear) that the truck reaches 2700 rpm it begins to jerk-feels like you’re trying to start it in 3rd gear instead of first. We have had it in a shop with someone who just repairs Nissan’s and have been unable to find the problem for over a year. Have looked at the catalytic converter, fuel pump, and air flow meter…nothing has helped…

Give The Model-Year And Approximate Number Of Miles On The Nissan P/U Truck, Please.
This Does Have A Manual Transmission, Correct ?
Has The Truck Been Maintained According To The Manufacturer’s Recommendations ?


The pickup is an '86 Kingcab manuel transmission with 4 x 4 optional…has 166,000 miles on it. We have had it for 10 years-we have the oil changed other than that have not had yearly maintainence done…We use as a work truck-yard work ect…rarely driven…