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RobM626

Vibration that 2 mechanics and Mack dealer can’t figure out

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Most any R model whether on air or spring could be made to drive right but it takes time, understanding of the dynamics involved, and patience; all of which limit the needed funds expended to obtain the desired results. Centrimatics, (or similar) or good old lead weights along with any good method of balancing the rotating assemblies as units were a necessity for a well balanced truck. Driveline balance is always overlooked it seems but a driveline that spins front to rear with less than 25 grams of imbalance is very smooth to the complete truck. Seldom are they balanced that close in a driveline shop. I've seen new slips and splines which need improving right out of the box. The shop in Peoria knows what I want and I've never had a problem with them through several shaft changes/modifications, or builds. They all run true, but the guy doing the work and I get along great citing old trucks and that plays.

Most vocational trucks I've seen always have mud and dirt piled and caked up in the rims. This severely precludes balance from when things are clean and it's a big contributor to vibration issues I've been around. Funny about snow and ice in the winter doing the same thing and the vibration goes away if the truck is allowed to warm and melt off overnight.....

 

Edited by Rob

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1 hour ago, RobM626 said:

I know I can see that! So true... I really wish I came on here when the problem started...

im a perfectionist when it comes to cars, trucks, and guns lol. I like to take care of my stuff so it takes care of me

Remembering that you called yourself a perfectionist.....

The truck damage picture was spontaneous, but looks like it just came off a show, so confirmed. Tank looks like it gets polish once a week.......

Hard love questionnaire....

1. Have you had someone else run and interpret the shake? Other drivers? Mack owners?

2. Did they tell you definitively that "this is not natural or normal harmonics"?

3. Have others argued that this truck feels perfectly normal and operational?

 

I've put your posts together as one consolidated paragraph and read it twice.

IMO---- It just doesn't click. 

You may have what I dubbed "Seismograph A#%". We had operators with this condition who could tell you what tire had a rock pinched in the tread. You think it would be a blessing to be thoroughly connected to your machine and note every shake and hear every inconsistent sound, but it CAN be a curse in a meaty chassis like yours.    

While I was writing this Lmack dropped a post I think is going the same direction? Much more gracefully.                

 

 

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1 hour ago, Mack Technician said:

Remembering that you called yourself a perfectionist.....

The truck damage picture was spontaneous, but looks like it just came off a show, so confirmed. Tank looks like it gets polish once a week.......

Hard love questionnaire....

1. Have you had someone else run and interpret the shake? Other drivers? Mack owners?

2. Did they tell you definitively that "this is not natural or normal harmonics"?

3. Have others argued that this truck feels perfectly normal and operational?

 

I've put your posts together as one consolidated paragraph and read it twice.

IMO---- It just doesn't click. 

You may have what I dubbed "Seismograph A#%". We had operators with this condition who could tell you what tire had a rock pinched in the tread. You think it would be a blessing to be thoroughly connected to your machine and note every shake and hear every inconsistent sound, but it CAN be a curse in a meaty chassis like yours.    

While I was writing this Lmack dropped a post I think is going the same direction? Much more gracefully.                

 

 

I really try to keep it as nice as I can considering it’s an 18 year old truck... this picture was after I fixed it when the loader hit me . I painted the body and put lights in as well.

in regards to your questions

1. Other people can definitely tell there’s a problem but no one was able to pin point what exactly was making the noise, hence the clutch being replaced 3 times, the transmission, and pto. And Everytime I put a new clutch In it feels better for a couple days then that starts rattling and chattering like crazy.

2. I would say 75% of the people have said it was not normal and the other 25-% really don’t know their ass from their elbow to make an honest answer

3. Mack argued the truck was normal but by camshaft ended up being bad at that time so their credibility went out the door in my book

the first mechanic argued it was normal and I had 2 injectors that were shot and the truck was misfiring after he did the cam so his credibility went out the window to me

the current mechanic agrees something is wrong but he didn’t know what it was. But his boss the owner who doesn’t knowwhat to think

i will say this though whatever it is and I think I know what it is (crankshaft related) is getting progressively worst over time. Today I was driving and the truck is struggling with power.. I have no smoke like I did when the truck had bad injectors but just does not have the power it had... the vibration is starting to become banging and knocking. 

I may be young and may not have as much time in older trucks as some of you guys have. But I know my truck and I know that it wasnt like this a year and a half ago.

but you are right I feel like it is a curse hearing every little sound

 

D7E8BC07-1E95-4162-B6A9-FE2DC72F0DA6.jpeg

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1 hour ago, Rob said:

Most any R model whether on air or spring could be made to drive right but it takes time, understanding of the dynamics involved, and patience; all of which limit the needed funds expended to obtain the desired results. Centrimatics, (or similar) or good old lead weights along with any good method of balancing the rotating assemblies as units were a necessity for a well balanced truck. Driveline balance is always overlooked it seems but a driveline that spins front to rear with less than 25 grams of imbalance is very smooth to the complete truck. Seldom are they balanced that close in a driveline shop. I've seen new slips and splines which need improving right out of the box. The shop in Peoria knows what I want and I've never had a problem with them through several shaft changes/modifications, or builds. They all run true, but the guy doing the work and I get along great citing old trucks and that plays.

Most vocational trucks I've seen always have mud and dirt piled and caked up in the rims. This severely precludes balance from when things are clean and it's a big contributor to vibration issues I've been around. Funny about snow and ice in the winter doing the same thing and the vibration goes away if the truck is allowed to warm and melt off overnight.....

 

I hear ya the r models weren’t built for comfort but I have driven some that drove pretty nice. Mine was one of them.we have my 2000, an 04 granite and 06 granite and a 2012 granite. So I’m aware that the rd doesn’t ride like those trucks . It doesn’t have an air ride cab. You feel every little bump. The body banging is always making noise. But I definitely know when something isn’t right. The rest of the truck really is almost perfect. I put the truck up on stands and the driveshaft and tires run beautiful

Edited by RobM626

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1 hour ago, Lmackattack said:

I will also make a comment about R models in general . Some were rock solid and drove as smooth as other trucks. then you had some that felt like they spent more time in the air than on the pavement. Most 6 wheeler Macks I drove were well planted to the ground and were smooth driving and running with that extra weight of the dump bed took out any engine vibrations. A superliner with air ride cab was quieter than a standard R model with air ride cab etc...My experience it was the R model tractors was that would tend to vibrate more.  What im getting at is these R models all had more vibration than a modern day truck or one made of aluminum.  ones opinion of a "bad" vibration may be completely normal to someone else. And without one being there to see or feel it its best to get a few opinions on it. 

 

I agree 100%. The rd was Nice but on the primitive side. It was like 80’s 90’s technology

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1 hour ago, RobM626 said:

I really try to keep it as nice as I can considering it’s an 18 year old truck... this picture was after I fixed it when the loader hit me . I painted the body and put lights in as well.

in regards to your questions

1. Other people can definitely tell there’s a problem but no one was able to pin point what exactly was making the noise, hence the clutch being replaced 3 times, the transmission, and pto. And Everytime I put a new clutch In it feels better for a couple days then that starts rattling and chattering like crazy.

2. I would say 75% of the people have said it was not normal and the other 25-% really don’t know their ass from their elbow to make an honest answer

3. Mack argued the truck was normal but by camshaft ended up being bad at that time so their credibility went out the door in my book

the first mechanic argued it was normal and I had 2 injectors that were shot and the truck was misfiring after he did the cam so his credibility went out the window to me

the current mechanic agrees something is wrong but he didn’t know what it was. But his boss the owner who doesn’t knowwhat to think

i will say this though whatever it is and I think I know what it is (crankshaft related) is getting progressively worst over time. Today I was driving and the truck is struggling with power.. I have no smoke like I did when the truck had bad injectors but just does not have the power it had... the vibration is starting to become banging and knocking. 

I may be young and may not have as much time in older trucks as some of you guys have. But I know my truck and I know that it wasnt like this a year and a half ago.

but you are right I feel like it is a curse hearing every little sound

 

D7E8BC07-1E95-4162-B6A9-FE2DC72F0DA6.jpeg

If you are having banging and knocking you better have a tow truck on speed dial!! When what ever finally gives up you will know what is wrong.   terry

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if you think it is crank related you might try to bar the engine back and forth and see if the flywheel is moving at the same rate. if you have any slop at all. there is your issue.

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5 hours ago, Lmackattack said:

if you think it is crank related you might try to bar the engine back and forth and see if the flywheel is moving at the same rate. if you have any slop at all. there is your issue.

I just did it this morning and I have some play. I’m not sure exactly how much BC I don’t have a dial but it’s definitely more than a few thousands of an inch. Hopefully I can get the truck in shop before week end.

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7 to ten thou would not be unreasonable! 

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Yup. If it's over .015", you got problems.

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On 3/15/2018 at 10:28 AM, Rob said:

Yup. If it's over .015", you got problems.

Checked endplay with dial it’s a .010”.

run out was at zero. I changed the cam and crank position sensors and the studder when returning to idle seemed to get better... I still think I should maybe pull the pan and have a visual inspection of the bearings 

there’s a few other things that I want to check out too.

one more thing that I found strange was when I scanned the truck with computer it was sending codes for air mass flow sensor and an egr related code both of which my truck doesn’t have. Aren’t the codes for ASET/AI motors? Why would my truck me sending those codes?

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Did someone change the ECU when you weren't looking ??? defiantly wrong codes for that engine ! We ran into this last week someone changed an ECU and didn't Reflash the thing kept derateing  at 33 psi programed for a WASTE GATED turbo  No waste gate on this unit! Reflashed it All is good !

You may want to have the dealer reflash the ECU and see how it is after! May just be the ticket!

Worth tring in my mind!

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59 minutes ago, fjh said:

Did someone change the ECU when you weren't looking ??? defiantly wrong codes for that engine ! We ran into this last week someone changed an ECU and didn't Reflash the thing kept derateing  at 33 psi programed for a WASTE GATED turbo  No waste gate on this unit! Reflashed it All is good !

You may want to have the dealer reflash the ECU and see how it is after! May just be the ticket!

Worth tring in my mind!

When I saw those codes and looked them up that was the exact thought that went thru my head . Maybe u were saying it joking but I seriously thought it.

My mechanic mentioned “it seems like the truck lost it’s memory” 

forgive me if I’m not as technically inclined as you guys but is that a possibility?

does mack charge to reflash ecu? How long does it take?

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Of Coarse ,what ever the shop rate is for that job at that shop !do you have a dealer near by? if so I highly recommend you check into it !

yes I was kidding around a bit  however I was suggesting that unless you bought the truck used and were u sure of the history then this maybe the case .unless someone pulled a fast one on you! recently at a shop you visited!

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9 hours ago, fjh said:

Did someone change the ECU when you weren't looking ???

Sounds like whoever repaired the Front end when It got wacked..very kindly "lent" you another ECM as well..:wacko:

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There use to be a lot of that going on at our shop, but the rule was stealing from a used truck on the line was fine.......never touch customer. Nice to have a spare ecm around when trying to dispel an  issue.

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8 hours ago, fjh said:

Of Coarse ,what ever the shop rate is for that job at that shop !do you have a dealer near by? if so I highly recommend you check into it !

yes I was kidding around a bit  however I was suggesting that unless you bought the truck used and were u sure of the history then this maybe the case .unless someone pulled a fast one on you! recently at a shop you visited!

Yes I do have a dealer a few mins away. I’m going to look into it this week.

should I just ask for a re-flash and any updates if any?

we bought the truck new in 2000.

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5 hours ago, Hayseed said:

Sounds like whoever repaired the Front end when It got wacked..very kindly "lent" you another ECM as well..:wacko:

😤 I wish I could know for sure

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5 hours ago, Mack Technician said:

There use to be a lot of that going on at our shop, but the rule was stealing from a used truck on the line was fine.......never touch customer. Nice to have a spare ecm around when trying to dispel an  issue.

Can mack tell if the programming is wrong by hooking it up to their computer? Other than codes coming up that aren’t relevant to my truck? 

Is it a quick job or do you think I need to leave the truck there for a day or 2?

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2 hours ago, RobM626 said:

Can mack tell if the programming is wrong by hooking it up to their computer? Other than codes coming up that aren’t relevant to my truck? 

Is it a quick job or do you think I need to leave the truck there for a day or 2?

You will likely get charged An hour shop time! just guessing on that!

Usually  what Mackteck said there is the case AS A RULE u don't swap a customers ECM out with out asking him if it is alright to do so if your using it to check somthing on another vehicle ALWASYS put it back! however people do stupid shit some times!

What ever was in your truck data file last time it was flashed will go in to that Ecm including the CAL codes for your unit pumps There is a slim chance That These MAY be causing your other issue . the cal code being different RARELY  affect the Engine Running  rough But however anything is possible! So As long as that dealer has the old mack software its worth a shot! in my mind!

The Reflash with tell you only that the DATA is (Different Or the SAME)  and it will  ask    Do you still want to proceed !  you cant see what is different! in most cases  We always say proceed just in case they slip something in after the fact in the main frame ! Cases where we Don't Reflash is on early model 460xt engines that had the Extra Torque Engine File AS U MAY never get that engine file back! They were very stingy with it!

Edited by fjh

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25 minutes ago, fjh said:

Usually  what Mackteck said there is the case AS A RULE u don't swap a customers ECM out with out asking him if it is alright to do so if your using it to check somthing on another vehicle ALWASYS put it back! however people do stupid shit some times!

What ever was in your truck data file last time it was flashed will go in to that Ecm including the CAL codes for your unit pumps There is a slim chance That These MAY be causing your other issue . the cal code being different RARELY  affect the Engine Running  rough But however anything is possible! So As long as that dealer has the old mack software its worth a shot! in my mind!

The Reflash with tell you only that the DATA is (Different Or the SAME)  and it will  ask    Do you still want to proceed !  you cant see what is different! in most cases  We always say proceed just in case they slip something in after the fact in the main frame ! Cases where we Don't Reflash is on early model 460xt engines that had the Extra Torque Engine File AS U MAY never get that engine file back! They were very stingy with it!

Now that you mention unit pump CAL codes I wonder if the codes were even put in right when the new unit pumps were put in . That wasn’t done at mack... I’m gonna stop by the dealer this week and see what I can do... I just hope they don’t make me leave the truck another couple days and that they don’t slam me with a 1-2000 dollar bill... I remember when I asked about getting a re-rate to 400hp they said it was around $2000 and they haven’t done those In years.

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32 minutes ago, fjh said:

Usually  what Mackteck said there is the case AS A RULE u don't swap a customers ECM out with out asking him if it is alright to do so if your using it to check somthing on another vehicle ALWASYS put it back! however people do stupid shit some times!

What ever was in your truck data file last time it was flashed will go in to that Ecm including the CAL codes for your unit pumps There is a slim chance That These MAY be causing your other issue . the cal code being different RARELY  affect the Engine Running  rough But however anything is possible! So As long as that dealer has the old mack software its worth a shot! in my min

So when we uproot unit pumps we number them. if that wasn't done then you have no clue where they went back in! in this case you need to confirm the cal codes on the pumps and reenter or confirm them  IF YOU CAN EVEN READ THEM  they may not even be READABLE NOW (Not positive on this)  But  I do believe you can see what is in the cal code area on the screen when you go in to change a cal code! Mack teck or mack pro may remember!?? 

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1 hour ago, fjh said:

So when we uproot unit pumps we number them. if that wasn't done then you have no clue where they went back in! in this case you need to confirm the cal codes on the pumps and reenter or confirm them  IF YOU CAN EVEN READ THEM  they may not even be READABLE NOW (Not positive on this)  But  I do believe you can see what is in the cal code area on the screen when you go in to change a cal code! Mack teck or mack pro may remember!?? 

Alrighty... gonna see what happens ... thanks bro

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As a word of advice...for the sake of getting to the root. cal codes are not able to reduce run quality in an obvious manner. At least I never experienced it. They(codes) are justified as an emissions requirement, but dont affect the running performance enough to be noticed. 

Not saying to ignore them. You should have them properly installed to the ECM for good practice. Just don’t expect that if I mixed your codes around intentionally, that you would leave my shop and have any clue I did it. They engineer that redundancy into calibrated injector engines so you can service them in the middle of the oil field, asphalt dump, concrete pour, etc and calibrate later...... to get you past “machine down” situation. 

Edited by Mack Technician

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13 minutes ago, Mack Technician said:

As a word of advice...for the sake of getting to the root. cal codes are not able to reduce run quality in an obvious manner. At least I never experienced it. They(codes) are justified as an emissions requirement, but dont affect the running performance enough to be noticed. 

Not saying to ignore them. You should have them properly installed to the ECM for good practice. Just don’t expect that if I mixed your codes around intentionally, that you would leave my shop and have any clue I did it. They engineer that redundancy into calibrated injector engines so you can service them in the middle of the oil field, asphalt dump, concrete pour, etc and calibrate later...... to get you past “machine down” situation. 

But having improper ecm programming can definitely affect run quality correct? 

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