do you have to take the moter out,to do a ring job.
No, the job is easier if the motor is out of the truck but can be done either way.
Generally, yes. There are some cars or trucks that this can be accomplished without removing the engine, but nothing modern that I know of. What year and engine option are we talking about for your Nissan?
If you need a ring job, you’d be better off removing the engine and getting the cylinders machined to uniform size. A lip develops over the years that needs to be removed, and any irregular wear will make your ring job a wasted effort. I’ve done a ‘rings only’ job (engine left in car) twice, with continued oil use the result. Improved? Yes, but it would have been better to do the whole job.
You would be FAR better off finding a serviceable engine in a salvage yard then trying to do a “ring job”. If it needs rings, it needs EVERYTHING…Don’t waste your time and money doing partial overhauls…
In the 1940’s through the mid 1960’s, it was quite common to put rings in an engine that was still in the car. There were a few exceptions where the pan couldn’t be removed without taking out the engine–the postwar Studebakers were one such car. Sometime around 1961, it was no longer possible to drop the pan on the 6 cylinder Chevrolet without pulling the engine. In this time period, it was much more common to replace the piston rings with what were called expansion rings for oil control, break the glaze on the cylinder walls with a honing stone, gring off the ridge at the top of the cylinder and grind the valves. This quickie “overhaul” might gain the owner 20,000-30,000 more miles out of the engine. If the engine didn’t have to come out, this made this type of overhaul much quicker.
However, even in this time period, “remanufactured” engines for many cars were available from Sears and Montgomery Ward as well as other places and this really was a better way to go than a sloppy patch. Today, it makes even more sense to go with a remanufactured engine instead of a quickie overhaul.