grinding noise at high RPM?? 7.3L PSD

volcomsurfer

Adventurer
As I was driving through Neveda last week I experienced some long hot inclines. At about 70 MPH at about 3k RPM and up I'd hear a grinding type noise. Sounds kind of like a ball bearing or something. I could get it to stop if I peddle it and go to a lower RPM and it would come on when I turn OD off and it would downshift. Anyone experience this or could point me in the right direction through that info? I can recreate it so I might get someone to drive out with me.
 

VOODOO7.3

Adventurer
Volcom, can you post your mileage and a little more info on your van. If you lost power, you could have popped off a turbo boot. (There are two rubber 3" dia. x3-4" long hoses connecting the turbo compressor outlet to the top of each manifold.) They get oily inside and can pop off during a hard push. If that's what it is, clean them off by soaking in soapy water overnight. Then dry them off and re-install. You want the hose clamps fairly tight, but DO NOT overtighten as you can crush the manifold intake tubes. I know it is 7.3, 4R100 transmission, but it is really hard to help you out without actually hearing it, or knowing what's been done (or not). I would recommend at least pulling over, removing the dog house cover, checking all fluids, and also checking all bolts, clamps (on turbo, down pipe, manifold boots, air intake hoses, air filters, etc. You have to remember that all the additional vibration from the diesel means that everything should be checked and re-torqued if necessary. I found 3 of the huge main bolts not even finger tight on a friend's transmission! Also make sure you always let that diesel idle for 10 minutes after those long hard runs (as opposed to pulling over to eat and shutting it off quickly). It allows the turbo to cool down properly. Hope that helps. Post back updates or new findings and I'll try to help you out. -Jason
 

volcomsurfer

Adventurer
Thanks. I'm at my girlfriends house in salt lake so it's a perfect time to go through the whole thing anyway. I just ticked over 250,000 on that stretch. It didn't feel like it was losing power at all. I think it is going to be tranny related. How often do you guys change the fluid/filter on these?
 

Ozrockrat

Expedition Leader
AC clutch or idler pulley. But the cooling fan clutch is also a good candidate. Go to harbor freight and get a stethoscope and have a listen at idle to all the rotating parts you can.

Start with simple/ cheap before heading down the web inspired complex / expensive problems.
 

IdaSHO

IDACAMPER
These motors are so noisy, even at idle, even with a stethoscope it can be difficult to pinpoint.

If it is accessory related, you are actually better served by simply removing the serpentine belt, and spinning things by hand to find the suspect pulley/bearing.
 

Bikersmurf

Expedition Leader
I'd agree that these engines are noisy... to the point that dying bearings on the front of the engine go unheard.

FYI, the two idlers and the tensioner all use a standard, easy to find, sealed bearing... 6203 if I remember correctly. I replaced all 3 for around $20. I carefully tapped the new bearings in using the old one to drive it in. After installing it on the engine I carefully tapped each and spun and tapped till they ran true. With a press, they'd likely need less alignment adjustment.

If in doubt, Replace them.
 
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VOODOO7.3

Adventurer
Thanks. I'm at my girlfriends house in salt lake so it's a perfect time to go through the whole thing anyway. I just ticked over 250,000 on that stretch. It didn't feel like it was losing power at all. I think it is going to be tranny related. How often do you guys change the fluid/filter on these?
Volcom, glad to hear you are someplace safe and not on side of the highway. Trans fluid change interval is 30K miles. Ford claims filter inside trans pan is lifetime, but Mark K recommends replacement every 60K. If you have the stock van pan, then you need the shallow filter. If UJoint put in a 4wd truck transmission, it has the deep pan filter. There is probably a Magnefine in-line filter inside bumper before cooler, change it out every 10K. At 250K, you are over due for turbo rebuild unless it has been done by PO. Transmission pan bolts get torqued to 11 lb. ft.. Here's how to change your ATF, from a Ford engineer who knows the 4R100 better than anybody:
http://www.ford-trucks.com/article/...F_Fluid_in_a_E4OD_and_4R100_transmission.html
Random thought -were you in 4wd someplace right before that noise started? Just wondering if one or both of your hubs was still locked up. Ask me how I know that noise, haha! Just to be sure, I put it in reverse about 20 ft. after unlocking then drive.
Hope that helps you out! -Jason
 
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