jerrymac

Regarding the minor oil seepage at the pinion housing, have you checked the vent cap on the carrier to make sure it isn't plugged? When the oil gets hot it expands and the pressure has to go somewhere. That somewhere is usually out through a wheel seal, pinion seal, or maybe in your case the pinion housing shims. Just a thought.

It's not uncommon to have to 'excite' an older style alternator before it begins to charge, but ten seconds seems a little excessive. You might just want to update to a newer style alternator that doesn't need to be 'excited' any more to charge. Otherwise, if you have a complete VIN, I can probably get one of our parts guys to look it up and tell you what alternator came on your truck originally , if Volvo will still give them access to 1977 R Model parts. Since Volvo bought Mack, it is getting really hard for our guys to look up parts for older Macks. Since Volvo trucks don't last more than 4 years before going to the bonepile, they can't seem to understand why people would be looking for parts for 30 year old Macks. Volvo has fixed that now though, as they now guarantee that no Mack built after January 2007 will last more than 4 years either.

If you have never rebuilt a Mack differential, here are just a few things to keep in mind. Make sure you retain the original shims from the pinion housing and spur shaft housing, as these are there to set the gear pattern on the ring and pinion gears. If you toss them you will be a long time setting the patterns. If the shims look good you can reuse them. If they are badly rusted/corroded make sure to replace them with the same overall total thickness of shims. Also reuse the spacers on the pinion and spur shaft as a starting point for checking the bearing preload on the subassemblies before installing them. The thickness of the spacers is stamped on the edges and this will give you a good idea of what you might need if the preloads are too loose or too tight. Also, make sure that the little tin tray with the magnets on it is still attached to the side cover. I have seen many of these crack around the bolt holes and fall off. Although the ring and pinion gears will chew it up without much damage to the gears, this little tray does serve a useful purpose. It collects the 'splash oil' from the pinion gear and then it drips down into the front housing on the thru shaft. The thru shaft(depending on the age of diff.) has either a piece of wound metal strip, or a wound casting on it that feeds oil to the power divider as it spins. If you find any metal in the axle housing, I would suggest installing a complete bearing kit as you might not be able to see any possible cup/cone damage. Kit comes with all the bearings and races , seals , gaskets etc. Also, while setting the preload on the bullgear, I always tap the race toward the gear with a hammer and punch as the spanner nut doesn't always seem to move it as easily as it should. Whew! Hope this helps.

It seems that Volvo must be using the Swedish alphabet to assign these letters to the Macks, since none are consistent. As a dealer mechanic I have been trying to learn 'Swenglish' for the past couple of years but it is starting to get ridiculous! Too bad Mack can't just buy itself back from Volvo. All would good then..

Check for bubbles in the Davco filter with engine running. There should be NO bubbles. If there are you might have an o-ring in the Davco unit leaking. Also check for any film of fuel, even minor at the connections on the EECU cooling plate, especially if the inlet side is the plastic push-on type fuel line. Since these are suction lines you generally won't find a noticable leak, but will let air into the system. Also, have you checked the fuel pressure with engine running? It should be about 50 to 85 p.s.i. Could be a leaking fuel pressure regulating valve. Oh yeah, by the way, does it ever seem to 'make it's own oil' ? If it does it could be a shaft seal on the supply pump leaking, or an o-ring on an EUP leaking.

Can't they look this up with the VIN of the truck? If you don't have the complete VIN, and the truck has the original framerails, the complete VIN should be stamped in the Pass. side rail just behind the steer axle between 2 lil stamped Bulldogs. Funny someone mentioned the old 'fish tape' , as one of our parts guys had to go upstairs to the 'old storage area' and look up some parts with them for a guy looking for parts for a 72 F model the other day. I don't know if they were able to help the guy, but, the parts guy was kinda laughing about still having to use the 'old fish tapes' to look up parts.

My guess is that they would under the same conditions, however I can't honestly say from my own experience. Since Volvo's have never been popular in this area, we don't even keep any in stock on our lot. We have been a Mack dealer for decades and Volvo for about 6 years now, and we have only sold 5 Volvos during those 6 years and they were older ones with D12's. It seems that the problem with the rollers/camshaft is mainly occuring on trucks that have been sitting for some time and the rollers are seizing to the pin/bushing. When the truck is started it rather quickly damages the roller and cam lobe. It has happened to several of the new trucks we sold off of the lot with MP8's, however I can't say how long they may have been sitting on the lot as I don't really pay too much attention to that.

My guess would be that you could order it with the frame length and wheelbase for the application of your choice. I say this because our local DOT has new MR's with line painting equipment mounted on it, and one with a huge bridge inspection body on it, and one with a tanker and spray equipment for tar and chipping roads. I believe Mack refers to them as the Refuse series simply because that is the most common use for them.

As a longtime dealership mechanic, I would like to offer my congratulations to Mackdaddy on his quest for a new Mack Pinnacle Rawhide. They are indeed a nice looking truck. I hope that they get all the 'bugs' worked out of the MP8 engine before yours is built. They have already made some changes to address the problems with the copper injector cups, and it is my understanding that they are currently working hard to address the problems with the rocker roller/camshaft failures that have been an issue on the MP8's. They got the 'bugs' worked out of the MP7's rather quickly and they seem to be holding up well. Hope they can do the same for the MP8's. Although I could be wrong, I have been before, I don't believe that the Pinnacle is available with the new MP10. If it was, it would be great truck with available 600 H.P. Huh. As mechanics, we don't get much info on the new , up and coming offerings by Mack, just the known issues. We are like mushrooms, they try to keep us in the dark, and feed us s**t.... Good luck on your new truck, I hope it serves you well...... By the way, I don't know how you guys can make a living with the price of fuel over $4.50 a gallon. You certainly have my respect in your business knowledge to be able to keep delivering the things we all need at such a high cost to you in getting it to us. Keep up the great work....

Salesman have a great way of twisting the meaning of things,lol. Mack doesn't make an engine designed to run on Ultra Low Sulfer Diesel Fuel. Hence the U in your example above, CXU613 is as I had stated earlier. The U means that it is equipped with a VOLVO engine. When the new EPA regulations took effect for 2007 , Volvo discontinued the Mack engine. All Mack-branded trucks built after that had Volvo engines, built at the Volvo powertrain assembly plant. The Mack MP7, MP8, and MP10 are identical to the Volvo D11, D13, and D16. Depending on which engines are needed that day, they simply change the paint barrels at the end of the line. If Volvo needs engines, they paint them green, if Mack needs engines, they paint them red. Also, the Mack branded CH and CX trucks are also now built by Volvo at Volvo's assembly plant. I believe that the Granite is still assembled in Hagerstown though, at least for the time being.

Have a compression test done. Should be at least 400 p.s.i or better on a sound E6 and about 500 p.s.i.on an E7 engine. We usually do a quick check first with the manometer. Shouldn't be more than 1" of crankcase pressure under hard pull. Oil consumption is also a good indicator of engine condition. As a side note. Although less common, a bad air compressor can leak air past the rings and create pressure in the engine crankcase, as can a bad turbo that can force boost pressure down through the oil return tube and into the crankcase.

Unfortunately I can't tell you how to reset the idle using the cruise buttons, but i can tell you that alot of drivers seem to somehow screw up the idle with them . It only takes a couple of minutes to reset the idle by a dealer. we just hook up a laptop and change the vehicle parameters. It only takes a few minutes , and I have done this for people many times at our dealership free of charge, since it would take the service writer longer to generate an RO than it would to do the job, so we generally do small things like this as a goodwill service to our customers. I will however leaf through the VMAC III service manual to see if it can be done with the switches , and how. It might be easy, I just never tried it since we use laptops for all the electronics.

You could probably contact Mack to get on their BullDog Magazine mailing list, or ask your local dealer for a copy. We usually recieve a couple dozen at our dealership and give them to customers. Or, if you want to just read them all right now, you can simply go to Mack's website @ macktrucks.com and click on the site map. Scroll down about halfway and look for Bulldog magazine. You can read the last 6 or so issues in PDF format. You will have to enlarge them though to read them since they look kinda small by default..

PRE- volvo. The BULLDOG was only 4 inches high, but looked up to by an entire industry. Now the Bulldog, with tears in his eyes, simply shits on the hood of a volvo, and unfortunately, there is nothing that you , the owners, or me the dealership mechanics, can do about it.. Simply put, volvo don't care about you, they only care about themselves. They don't care if your new truck falls apart at 320,000 miles cause the warrenty is up. They don't want you to keep your truck past 3 years, they want to to send your money to Sweden every 3 years for a new truck. Bottom line; volvo bought Mack to get access to its large number of dealerships, thats all. They don't care one bit about Mack's history, or it's longtime owner loyalty, they only wanted their dealership base to peddle their junk.

Amen!! As a mechanic at a Mack ( and now volvo ) dealership for nearly 2 decades I have seen firsthand, the Rapid decline in Mack trucks over the past 3 years. From what I see everyday, the only Mack parts on the new trucks is the cab shell and the Bulldog on the hood. They are built on volvo platforms, with volvo engines, volvo interior, and volvo electronics. Sadder yet, is the fact that today June 4th I brought a new Molvo CH in to do a predelivery on it before the customer picked it up and it had a noise in the engine. Imagine how our salesman felt when he had to call the customer and tell him that he couldn't pick up his New truck today because, we were tearing it apart to put a new camshaft in it. Yep, brand new MP8 with 65 miles on it and it had a cam failure due to 2 siezed intake rocker rollers. Sadder yet, is that volvo told us that it is 'normal' for the rocker rollers to sieze up if the truck has not been run for a few days. What are we supposed to do as a dealer? Go out every day and start all the trucks so that they don't fall apart in the lot? I am sure that all of you longtime Mack owners don't want to hear it, but the fact is, Mack is Gone. Do yourself a favor and keep your old Macks till you retire.

If memory serves me right , I believe that the battery ground on the Midliner goes to one of the bell housing bolts. where I remember seeing alot of problems.

HK is right. The new model designations are a Swede thing. The CH and CX built on a VOLVO platform are now a CHN and CXN , with the N meaning it has a Volvo frame. The U designates that it has a Volvo engine. I am sure that most of you know that Mack no longer makes an engine, so they will probably drop the 'U' soon since all Macks built after Jan. 2 2008 have Volvo engines in them.

We haven't really seen any major problems with the MP7's so far at our dealership. They seem to be holding up pretty well. It is the MP8's that seem to be coming apart in large numbers. We also had several of the Volvo D13's towed in this week with piston failures, and as you guys probably know, the MP8 and the D13 are identical except for the color and the module software and data files. We also haven't seen too many of the D16's yet with any major failures, but they are still kinda new out , so it might be too soon to tell, but if the 16's continue to hold up well, than it might be that the new MP10's will be a good engine also. These are just my opinions from a dealership mechanics point of view. Those of you that own or drive them might have a different opinion of them than I do. I just fix them, I don't own or drive them.

I hope your buddy isn't planning on using this truck to make a living. The Volvo MP8 engine seems so far to have about a 4% reliability rating. In other words, 96% of the new Volvo MP8 engines have failed. I know this from experience since I have wrenched at the same Mack dealer for nearly 2 decades. Our local DOT bought 20 new Volvo Granites last fall and none of them pushed a snowflake this past winter cause all of them were sitting in our lot waiting for new engines or camshafts. All of them failed with less than 1000 miles on them. So far, I haven't seen a single new Volvo MP8 run past 6000 miles without a major failure.