Have to RANT!!

The Pete I have been running has been a POS for the last four weeks, started throwing code 21 after quite a few derate adventures then flying right and code 55 or NO code stored. Then finally latched up 21 code, generic hi/lo 5v reference. OK all was fine just would have its moments of a little derate then be fine for literally Days. Owner took it into the shop for the code as was getting worse, tried a harness first as the connector ends were corrupting and falling apart, no change, tried a couple 'Known Good ECM' that one still showed the 21 another did not so opted for a processor. Did a set of rear drive brakes, a full lube, rt frt wheel bearings had some play so adjusted and other minor stuff. Go to get the truck code 21 was gone, in its place codes 25 and 46, find out the ECM replacement would NOT pre-program as to a glitch from the old one, at that time the shop found a bad Fuel Temp sensor at ECM and bad Atmospheric Pressure Sensor so swapped those out. Stayed in Derate, finally suggested we take to CAT Columbia MO for program checks and to find TDC the ECM was not doing well to find.

Get to CAT, spend the ENTIRE day floundering with a derated will not ramp up to HP issue where they find a bad Boost sensor on the intake and a bad oil pressure for the ECM off the engine, ordered both, they installed a spare Boost unit off a take out engine until ours would come in. Made mention of the Coolant Sensor showing -40 at full engine temp and fuel pressure being low compared to manual gauge on dash.

So we take the truck, I get two loads, have to run the engine fan in manual off the dash switch to control temp, find that below 160 degrees the codes stay away, above and they are machine gun repetitious with a squealing check engine alarm I can silence by letting off throttle and rehammering the engine.

Gets better, Was told by the independent shop foreman could have a bad set of sensors as seems like a lot going bad at once his recommend replace ALL. Next day as usual crank it for 45 seconds (75 degrees out) to get it to fire then starts as if nothing wrong, first thoughts was ECM could not find or see TDC and been getting long crank warm weather starts, Cam Position sensor is crap. Do a truck inspect all looks good save some spilled lube at the rt frt wheel they adjusted, hub cap still full, cleaned the mess to keep DOT off my a$$ and off to ADM with a 50K load of really dry beans. Get 40+ miles from yard can smell a little gear lube, figure the ooze of rt frt getting on drum, maybe and stinking, get to US 50 and I44 head E, smoke starts as I get to speed, odor is now ripe. Check engine alarm is bugging the crap out of me so I get off at MO100 and stop. Front Diff SMOKING hot, oil is everywhere, sprayed out of vent all over rear brakes, duals, banjo housing and front unit SCREAMING hot. Managed to get into a independent shop, put fans on it, they have to weld a nut to the fill plug to get it out, Meritor 40K RT. Still has oil in it, drain and refill, replace the filter and off to ADM. Got beans off, engine alarms are still driving me nuts, ALL engine parameters normal. Got it to Peterbilt OFallon MO. and stopped!!

Now it gets really interesting;
Shop gets the truck in next morning, calls owner, oil is cooked, and low, needs to have diff pulled, we already knew that. Right side carrier bearing was failed, spun in bore, metal everywhere, dig deeper and right diff side gear in five pieces. I drove it in for 140 miles broken, the mechanic kept telling the Owner No Way.

While this is going on I had called the independent garage, with the failed sensors they changed, the additional failed units coming and the hard start with the -40 engine temp we concurred time to change ALL the Damn sensors. I call CAT, give engine s/n, explain need ALL but atmospheric and ECM fuel temp sensors, any or all seals, any change hardware as to connectors whatever is updated put in a bag. Told had ALL.

Next day go to CAT ON MY OWN TIME, pick up a large bag of stuff, did not sit and inventory as I had never had issues from here prior and these then se in the owners car for the weekend. Owner called Pete, they agreed to install all the sensors with them doing the diff work.

Diff got there yesterday afternoon, NONE of the sensor O-rings were in the bag, nothing I had specified was really in the bag and the Cam position sensor was marked BO not in the bag. Pete had one in stock, had the orings and volunteered them at cost, so today they install the diff, that done start on sensors, Replaced ALL EXCEPT the ones that Looked newer to them. Parts department had a Boost sensor so owner had them install that and they did a test drive. Fuel Pressure was reading low on laptop, 45#, gauge on dash showed 75#, they had issues with fan not starting and that attributed AS WE ALREADY KNEW to the old coolant switch they DID NOT SWAP as appeared newer. Were certain needed a engine fuel pump due to the low numbers but had NOT put a manual ga on it to verify, then explained had the code 21 back and could attribute that to the coolant temp switch they had in hand but did not change!!

Owner was beside himself, did not understand all the run arounds by THREE shops, no one seems to give a flying F__K as to how to fix or what when told to, to install as to parts.

Me I just have to rant as I knew what needed done, had been there to give instruction on what to get done and was also dually ignored. Bad parts people, bad or worse shop management, bad or worse wrench benders dragging out what should have been a cake walk job.

Out of seven sensors, Seven checked BAD with that noted something has to have occurred either the old ECM 5v circuit went hard system voltage or the unit was exposed to a close lightning strike to affect all of these at one time.

ARRRRRGGGGH!!!!!!!!

Lot of cooks in the kitchen on that one. Has or did anyone do some welding on that rig recently and/or didn't remove the battery cables? Just wondering.

Truck Shop

Have been all over the monster since February, no welding during these last months, none I am aware of prior up to the owner purchasing it just at a year ago.

Electrical/sensor issues can be frustrating. I went round and round with a detroit 60 series last spring. We beat our heads against the wall for quite a while changing sensors, chasing possible fuel issues, harnesses etc. I finally had it taken to the dealer after on and off problems for a couple weeks. Truck would just die, without throwing codes, and randomly start and run fine- really frustrating.

I think I paid for 8 hours of dealer mechanics time, and 2 wires 4' long. Had a bare spot in a wire behind the air compressor. I think the best thing when multiple people are working on something is to keep a really detailed list of what's been tried- sometimes its just trial and error. I sent the truck to the dealer with a detailed one page list of everything we had tried and replaced. At least their mechanic could read the list and it would give him someplace to start.

The most frustrating thing to me, was the fact that there was really nothing wrong with the motor. It would run fine when it would run, and when it would die, it wouldn't stay dead. At least if it stays dead, you can know when you've fixed it. Random codes, sensor issues, etc. will drive me up a wall.

Hope you get it straightened out.

Just remember, all this electronic controls is "progress", making your life easier, because all you need to fix something is the computer. Hook it up to the truck and it will diagnose it and pop on a sensor and off you go. Just ask the design engineers.

If only it was actually that easy......

I hear ya CO, Was the main reason I walked out of the shops in 97, frustration over all the electronic crap to make life easier that become the chronic event I had to look at each day. Tooling, notably Lap Top diagnosis machines, upgrading software, constantly changing systems and theories, just got too old for a old dog like me. Then I start driving one of the damn things!! I guess too stupid to pick my battles properly!

Most of these wiring issues are caused by some early repair, mechanical or electrical. Instead of taking the time to secure and tie-up wiring, air lines or what have you
a number of people just let it hang and blow around and rub itself to death, fuel lines also. 75% of this stuff could be prevented with good skills.

Truck Shop

Truck Shop said:

Most of these wiring issues are caused by some early repair, mechanical or electrical. Instead of taking the time to secure and tie-up wiring, air lines or what have you
a number of people just let it hang and blow around and rub itself to death, fuel lines also. 75% of this stuff could be prevented with good skills.

Truck Shop

Click to expand...

I've replaced 3 or 4 harnesses on early 3406E's, just too much damage to repair and trust. Seem a few series 60's (early ones) Usually that was an issue behind the starter or the air compressor.

Hey Mr Miller, I'm considering selling my truck if your'e interested, A 1985 Scania P112H.Mileage unknown but heaps. All serial numbers same as build sheet.

Hopefully they get you fixed up and back on the road soon.Agree with Truck Shop.Wiring can only take so much heat and stress.Also makes me like B model Cats more and more

The harness was swapped first in this case, then moved to the ECM that was essentially going brain dead. CAT had the old one to pre-program the replacement unit but the program had failed to completely transfer for what ever reason and we had to take the machine to CAT from the independent garage for additional programming to get it beyond a derated limp mode. Cannot for any reason understand why the sensors are hard failing so rapidly and without any previous notated coded indications. Should know this morning when Pete opens at 7 if is ready or not.

I as so many are getting so frustrated with the current mechanics, parts countermen and other aspects of repair that just seem lacking any skills anymore so had to rant. Friend worked for a major airline, they cannot get aviation techs either, seems the pipeline for anyone with skills is dribbling to a no flow. Their last entry levels were ex-military service techs, found to be large component changers not very good at diagnosis nor spot repairs, just felt 'Owed' their positions due to being Vets. Very Sad as I saw that same attitude from Ex-Navy boys while working at the Nuke plant, the were 'owed' a job there as they were the ONLY capable(many not) persons TO work there.

Well, no news by now cannot be anything good. Pete has been open for almost a full hour, boss was going to call first thing so I have ominous feelings of this.

DMiller said:

Their last entry levels were ex-military service techs, found to be large component changers not very good at diagnosis nor spot repairs, just felt 'Owed' their positions due to being Vets. Very Sad as I saw that same attitude from Ex-Navy boys while working at the Nuke plant, the were 'owed' a job there as they were the ONLY capable(many not) persons TO work there.

Click to expand...

While I have all kinds of respect for anyone serving or have served in the military, my older brother did over 20 years in Air Force, the problem I saw at least in the few cases I was exposed to is that in the military everything is controlled by a set chain of command idea. Almost to the point that you may be authorized to drain oil but you need a different level of authorization to put oil back in then one level to remove filter and another to install. One guy who was looking for a job years ago mentioned he was "qualified" to install new injectors in a Detroit 12V-71 but had to get someone with more "authority" to adjust them!

Then there was the problem of knowing what he had worked on. He only knew things by the name or model of the military equipment they were working on, no idea of what the "civilian" equivalent might be. I guess if I had done a few years in the military myself I may have been able to talk with him better but it was almost like trying to ask someone a question who had no knowledge of the English language a technical question! I think the only thing I was sure of was he knew what a Detroit 2 cycle engine was anything else was a guess.

did anyone clean every electrical ground on the entire truck?

I believe that has been done.

While I respect the Service members and I DID serve long ago that is not a automatic in to any industry for my considerations. My Dad and Uncle came out of WWII radioman/navigators so could have done something with those trained skills but opted to learn Av Mechanics. Went to school for a year to learn what needed to be learned to get a good job. I did as well went to Ranken Tech for a 10 month crash course then thrown to the wolves in fleet work first off. All too many Nukes come out they fully understand the mechanism just do not acclimate well to civilian work much as the AF and Army brats that worked flying machines do not generally do well in commercial aviation. I had to release several "Tank Mechanics" that came to work at the Independent garage as could not get the hang of it, absolutely NO diagnostics skills and did not understand they needed their own tools as were always supplied in the military.

Still no call, almost afraid to call the owner as something has again thrown its ugly head around and he will NOT be happy. Lots of cash spent on a old wagon he may or may not be able to recover in short time.

Well the call came, truck WILL BE ready at first light of the morning. Actually will be ready any time after 8 tonight but the boss said morning will be soon enough. All is good, temp sender fixed 21 code and a FINAL fuel gear pump fixed a hard start they noted. Had a hub cap seeping so boss said Fix It and had a warranty to change the seal on the PD thrushaft as it started leaking on the road test.

Will see how it does in the morning.
Thanks all for the ears lent and bent!!

Well, STILL sitting and working At HOME. Went with owner to p/u unit, NOT done. Service foreman told him last evening would be ready last night and NOT done this morning. He is PO'd to say the least. Seems when swapped the front differential did NOT remove the thrushaft, I do understand is not a necessity but the rear end had cooked, the oil was cooked and metalized the thru shaft seal would have to be replaced AT A MINIMUM for my standards and No, they did nothing until AFTER the road test where the seal was leaking, got it apart(Yoke WAS Loose) and found a Necessary Spacer Sleeve is missing. Are trying to locate one NOW. How in the HELL does a mechanic get away with this? How does the shop management get away with this?

I am sick of the limited scope abilities of today's wrench benders, I ALWAYS looked at ALL the drive train if had a failure of this scope, no telling what else was damaged, bad, going to immediately after fail. This is nuts! Rant again complete For Now.

Almost forgot, was NOT a warranty fix, they never had that seal out, owner was mistaken thought it had.

Well, Larson Group decided they NEEDED to do something and make this Right. They scavenged a New Drive line and yoke as well spacer parts from a tradin sitting on the yard, they had made the repairs to it(Same differentials) around two months ago. They are making this right price wise as well as they KNOW bad word travels faster than anything good.

I thought you were retired. This sounds like someone else's problem...

Unfortunately, there is so little info on how to test these various sensors and so little training on how to actually diagnose the problems that most mechanics, even the good ones, end up loading the parts cannon and firing away.

In some ways, it's worse now that every shop has a "laptop" of dubious origin that they hook up to everything from a VW Jetta to a 15L truck engine. In the old days, if the change engine light was on, we sent them to Cat, Cummins, or Detroit "authorized dealers" as no one else could even get the software. Now, almost anyone can get in to the ECM and see what is what, but that doesn't mean they should.

I am but still active and FAR from Dead yet!! Was once a reasonable mechanic, fought my way thru the mud, oil and grease many long days and nights, still burn the midnite oil fighting with old machines I dearly enjoy as my own. Just binds my shorts to see the incompetence and the absurd disregard for customers in this day and age when there could be a decent earning for decent repairs.