HarryBiron093 Posted June 8, 2023 Share Posted June 8, 2023 I have 2002 RD E7 460. It’s been throwing the 3-4 code since I bought the truck 2 years ago. When I first got it there were no shims in the cam sensor. I replaced front and rear sensor. In order to get the light out and no stumble I needed 2 big shims and one little one. This year it needs another small shim to keep the light out. With this being said when it’s raining the truck runs worse but the code is never logged continually like a direct short. I sent the ECM out and got it rebuild with no help to the situation. I have verified via Mack Pro again thank you ! That my software is level 7 which is above the required per the service bulletin on the 3-4 code. I pulled the front cover today in hopes to find a worn thrust washer but I don’t see much wear on it. If you look at the picture youl see that it looks like the sensor is touching the the cam gear. Does the washer wear behind the cam gear where you can’t see it ? Anyone ever heated the gear and pulled it in place to avoid pulling the cam ? Help is much appreciated !! Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/ Share on other sites More sharing options...
fjh Posted June 9, 2023 Share Posted June 9, 2023 Nope the cam gear is a shrink fit on the shaft ! Unless you have a hefty puller it isn't coming of in frame! the cam code may have to due with front cover flexing check it closely for cracks seldom the issue how ever worth checking! make sure your motor mount id in good shape! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-532701 Share on other sites More sharing options...
Joey Mack Posted June 10, 2023 Share Posted June 10, 2023 Too add to the idea of removing the cam gear on the engine.. When the time comes to put it back on, you have to bake the gear in an oven to around 450-475 degrees, then quickly install it and 'seat-it' on the cam (cam standing up with thrust washer in place).. there will be know way to hold the cam and keep it from pushing into the block and the trust washer will fall and get between the gear and cam, also take the chance of pushing a cam lobe into a lifter roller. Yours is a 2002.. It may have ceramic roller lifters.. The lifter roller WILL crack..... 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-532748 Share on other sites More sharing options...
HarryBiron093 Posted June 24, 2023 Author Share Posted June 24, 2023 On 6/9/2023 at 8:17 AM, fjh said: Nope the cam gear is a shrink fit on the shaft ! Unless you have a hefty puller it isn't coming of in frame! the cam code may have to due with front cover flexing check it closely for cracks seldom the issue how ever worth checking! make sure your motor mount id in good shape! Thank you for the info ! Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533551 Share on other sites More sharing options...
HarryBiron093 Posted June 24, 2023 Author Share Posted June 24, 2023 On 6/10/2023 at 8:58 AM, Joey Mack said: Too add to the idea of removing the cam gear on the engine.. When the time comes to put it back on, you have to bake the gear in an oven to around 450-475 degrees, then quickly install it and 'seat-it' on the cam (cam standing up with thrust washer in place).. there will be know way to hold the cam and keep it from pushing into the block and the trust washer will fall and get between the gear and cam, also take the chance of pushing a cam lobe into a lifter roller. Yours is a 2002.. It may have ceramic roller lifters.. The lifter roller WILL crack..... As always thank you very much for the reply. I ended up pulling the cam (the correct way) and found very minor wear on the thrust washer. I put it back together with a new timing cover/sensor etc. ive been chasing this vibration for a while now and I thought it was coming from the transmission but it got a lot worse last week. I pulled the drain plugs and the rear rear pinion gear was coming apart. I change the rear end and the truck is smooth as can be. Also my 3-4 code dosnt come on but once in a great while and it has excellent power. What are your thoughts on a driveline vibration amplifying that code ? 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533553 Share on other sites More sharing options...
Popular Post Joey Mack Posted June 24, 2023 Popular Post Share Posted June 24, 2023 (edited) I have stopped many customers from fixing/replacing the tranny due to a vibe in the stick.... I have shown them many times it was a rear end gear issue, after ruling out U-Joints and carrier bearings, .. The drive shaft is a tube... It carries sound and vibrations.. as far as the Cam code... No connection in my mind,, (open to learn) I assume Mack 92-93 rears.. In the future... with Mack rears, drain the top reduction (9/16'' square plug at the lower left rear corner) and pull the cover to inspect the first reduction.. Bevel pinion and bevel gear.. look at the teeth for brinelling.. I have seen it many times... Keep coming here for free info and simple tests.. Jojo Edited June 25, 2023 by Joey Mack More content needed 3 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533554 Share on other sites More sharing options...
HarryBiron093 Posted June 25, 2023 Author Share Posted June 25, 2023 Yes sir when I popped the cover it was very clear lol you got it the information is much appreciated. Did you do much a/c work ? The symptom is vent temp is like 57 at best and low side is low high side normal. I’ve replaced evap/heater core/expansion valve/compressor/ dryer. Picture was at roughly 80degrees. I did loop my heater hose to make sure it wasn’t leaking by. Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533561 Share on other sites More sharing options...
fjh Posted June 25, 2023 Share Posted June 25, 2023 14 hours ago, Joey Mack said: I have stopped many customers from fixing/replacing the tranny due to a vibe in the stick.... I have shown them many times it was a rear end gear issue, after ruling out U-Joints and carrier bearings, .. The drive shaft is a tube... It carries sound and vibrations.. as far as the Cam code... No connection in my mind,, (open to learn) I assume Mack 92-93 rears.. In the future... with Mack rears, drain the top reduction (9/16'' square plug at the lower left rear corner) and pull the cover to inspect the first reduction.. Bevel pinion and bevel gear.. look at the teeth for brinelling.. I have seen it many times... Keep coming here for free info and simple tests.. Jojo Second that Joey ! I have saved a lot guys swearing they had a trans problem , from spending big bags of money by simply looking at diffs first before taring into tranys as they have wanted!Go with what you know first! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533562 Share on other sites More sharing options...
fjh Posted June 25, 2023 Share Posted June 25, 2023 wouldn't happen to be a 4:17 or 4:42 ratio would it ! ? couldn't hurt to check both diffs! just saying! 2 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533564 Share on other sites More sharing options...
Joey Mack Posted June 25, 2023 Share Posted June 25, 2023 Low side seems a little low.. did you weight the freon dose (#3) for a day cab...?? Did you put too much PAG oil in it?? 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533565 Share on other sites More sharing options...
fjh Posted June 25, 2023 Share Posted June 25, 2023 41 minutes ago, Joey Mack said: Low side seems a little low.. did you weight the freon dose (#3) for a day cab...?? Did you put too much PAG oil in it?? Not a Guru! An observation! How ever frost on the elbow can indicate a low charge ! Should be sweating a little just a bit damp! 2 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533570 Share on other sites More sharing options...
Mackpro Posted June 26, 2023 Share Posted June 26, 2023 On 6/24/2023 at 5:11 PM, HarryBiron093 said: As always thank you very much for the reply. I ended up pulling the cam (the correct way) and found very minor wear on the thrust washer. I put it back together with a new timing cover/sensor etc. ive been chasing this vibration for a while now and I thought it was coming from the transmission but it got a lot worse last week. I pulled the drain plugs and the rear rear pinion gear was coming apart. I change the rear end and the truck is smooth as can be. Also my 3-4 code dosnt come on but once in a great while and it has excellent power. What are your thoughts on a driveline vibration amplifying that code ? I believe your onto something there. Vibrations did cause 3-4 codes and Mack came out with a new front timing cover with casted in gussets around the cam timing sensor. I believe many many years ago I had a Eaton ultra shift truck and the centrifugal clutch was out of balance and caused a possible 3-4 code . I remember I replaced the clutch and it solved the problem. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533605 Share on other sites More sharing options...
Mackpro Posted June 26, 2023 Share Posted June 26, 2023 No gussets Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533634 Share on other sites More sharing options...
Mackpro Posted June 26, 2023 Share Posted June 26, 2023 Updated cover with gussets Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533635 Share on other sites More sharing options...
Joey Mack Posted June 26, 2023 Share Posted June 26, 2023 Once again,,, MackPro comes through.. Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-533641 Share on other sites More sharing options...
HarryBiron093 Posted March 1 Author Share Posted March 1 Good morning, I wanted to close out and reopen some issues from last year. Any help as always is much appreciated. The a/c issue with the expansion valve freezing up… I got ahold of a guy at Red dot that was extremely sharp. After doing some testing he told me that the expansion valve on those could be put in backwards. Sure enough that’s what it was. A/C works excellent now. The 3/4 code got a lot better for the majority of the summer after replacing the front cover but under load at 60-70mph it still throws the code on and off with power cut out. Some days it builds really good boost 35-38psi other days it dosnt build past 30. The 3/4 code comes on with a steady light when it rains heavy at night or while driving the truck in the rain. I finally had a chance to troubleshoot via the service manual for the electrical part in heavy rain. I found no shorts or any resistance readings that were alarming. At the end of the procedure it says replace the ecm. I did last year send it out to get rebuilt. To recap what has been done already. changed the ep and Rpm/Tec sensor both and 2 times/ checked ohms checked with depth micrometer and at the suggested Mack levels it should need no shims in the timing cover for the sensor. If you start it like that the 3-4 code is immediately on and the truck cuts in and out terrible. It was like this when I bought the truck. Truck runs the best with 2 .30 shims and one .15. Still cuts out on the highway. replaced front timing cover. replaced clutch and while i was in there I verified flywheel to cam timing per the book. had ecm sent out and gone through for $800 has anyone seen the rain affect a truck like this ? I’m at the point where I am going to run jumper wires out of the ecm to the sensors or replace the dampener (it’s 460hp so it has the bigger one) or buy a new ecm does anyone have a test one I could pay to use ? Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547448 Share on other sites More sharing options...
Joey Mack Posted March 1 Share Posted March 1 What is the condition of the engine harness? I read this back to last year, and didn't see where you checked all the grounds. I like the procedure for a 9-2 code. It points towards the grounds.. Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547449 Share on other sites More sharing options...
HarryBiron093 Posted March 1 Author Share Posted March 1 Joe, I have not checked grounds out side of what the 3-4 procedure calls for. On the 9-2 code diagram where does it call out the locations of the grounds ? BK-u-2.0 Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547450 Share on other sites More sharing options...
Joey Mack Posted March 1 Share Posted March 1 Batteries, the block ground in the picture, the ground breaker on the firewall (I have replaced these a few times), the ground behind the instrument cluster, the ground next to the fuse panel, the starter, Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547451 Share on other sites More sharing options...
HarryBiron093 Posted March 1 Author Share Posted March 1 I cleaned up the block ground and there was one on the frame rail right beside the block one that had 5 or so smaller wires going into it. I am not sure about the ground breaker on the firewall is it in the picture below ? When you say fuse panel is that the one on the top on the engine ? Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547454 Share on other sites More sharing options...
HarryBiron093 Posted March 1 Author Share Posted March 1 Do you think we are dealing with 2 separate issues on the 3-4 code one being when it rains and the other at high load high speed ? Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547456 Share on other sites More sharing options...
fjh Posted March 1 Share Posted March 1 did you clean the connections to on that night switch? and the battery's? Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547458 Share on other sites More sharing options...
Joey Mack Posted March 1 Share Posted March 1 That is the starter relay, the ground breaker is all black and looks like the starter relay. Look on the fire below the center of the windshields. Is this truck a CH or CX? Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547462 Share on other sites More sharing options...
fjh Posted March 1 Share Posted March 1 5 minutes ago, Joey Mack said: That is the starter relay, the ground breaker is all black and looks like the starter relay. Look on the fire below the center of the windshields. Is this truck a CH or CX? look down by the cab mount Joe!!! nit switch! ground fault has black wire I believe you are correct on the relay! looks like an R model! Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547463 Share on other sites More sharing options...
Joey Mack Posted March 1 Share Posted March 1 Dumb Me..... I see the outline of the cab where the hood comes down.. R model it is.. Quote Link to comment https://www.bigmacktrucks.com/topic/72930-3-4-code-e7/#findComment-547465 Share on other sites More sharing options...
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