I own a 02 Mack MR688s. I grease the U joints, Stearing joints, Shift youchs, Change the oil a couple times a year. I was wondering about the Drive axile bushings? are there any grease fittings, I can't find any. Or with this model is there anything I should watch out for? Any good tips like trani oil cooler cleaning. Any advice on keeping it running at its best? Any problems to look out for? Brake adjusters? Thanks. Brian

A good rule of thumb is every 300 hours do a complete service.All filters,oil,grease,boom grease.This is the spot where you catch things before it happens.As for the trunions,there just rubber bushings.Take a filter cart to the hyd oil while sevicing,at least a few hours helps.Drain hyd oil annually and clean tank.

That would be a great start

good luck

Many is right - grease grease grease - I had mechanic once back in the day that bet me I would not find all the grease zerts when I serviced my mack.  I bet him a six pack for every one I did not grease.  He found 18 that I missed and I thought I knew everything. (In the older Macks there was about 8 just on the seat)  Most of the fittings will be hard to find if no one has greased them in a while.  Just look at every moving part.

There are 2 grease fittings on each slack adjuster,don't forget the king pins.If you have a heavier suspension the trunnions will have fittings,most don't,they are rubber bushings like Mr.Many said.Treat your synchronizer properly by never range shifting while in neutral and grease the throw out bearing monthly with a high temp. grease.

I agree with not shifting the range selector in nuetral, but also, don't preselect too soo, either, or else the forks have pressure on them needlessly long. As for the throwout bearing, I disagree, there, unless you do a hell of a lot of driving and clutch every shift. Not likely, given that most pumps are not long-haul units, or on city delivery routes. When you do grease (for me, maybe once between oil changes and at O/C, Max 2 shots) grease sparingly, you don't want grease on your clutch plates.

Mack is a very funny animal on the rear susspension.If you have had problems with springs check with mack.I can't remember but if equiped with 38k rears you may wish to update springs to 40-44k.That should eliminate that issue.Also there's a susspension rod above the rear differentials,always check that for loose or movement.

Where to start the list and when to end it is the question...lol. Most of the major grease fittings have been covered in your suspension, steering, and drive line but also don't forget to make sure all of your breather caps are open and moving freely. There will be one for your tranny, 1 for the gearbox and 1 on each of the rear axles. Keeping these clear can help prevent seals from blowing out.

Thanks, good stuff. I figured out today when adjusting the auto adjust brakes, to tighten,then give it one full HALF turn out. With the auto adjust HALDEX it doesn't function corectly if it doesn't have enough travel. A quarter turn out like I was doing makes it try to readjust its self out which messes up the adjustment. I haven't looked for the throw out bearing zerk yet. King pin is good advice, and rear end cups makes sense. lets the moisture out i suppose. I take the oil from the hopper lube and spray the springs and frame from time to time to keep the rust down. Lee springs do brake. Oil might help. Also a little spray lithium on the moving parts under the cab.

The mr688 has been around for awhile. I would get a service manual for your year for truck. all 688's look the same but the tech. is differant from year to year.