98 Explorer 5.0/T18 Conversion Motor Vibration Help

[Antsun]

Hi All!

I followed a few threads on this forum with the Explorer 5.0 swap. I used the 164 tooth/50oz flywheel as recommended and everything fits up great. Issue is I have vibration coming from the motor (In neutral/not in motion) when I rev the motor past 2k.

Motor mount and trans x-member bushing are new and everything is torqued to spec and solid. Motor barley moves when the throttle is bumped.

Does the harmonic balancer need to be changed to support the difference in weight between the old flex plate and the new flywheel? I found one for the F150 motor but the pulleys are different and the F150 pulley belt location looks further away from the engine.

What else could cause the new vibration?

Any help or advice is greatly appreciated! Have a great weekend!

 

[Antsun]

Hi All!

I followed a few threads on this forum with the Explorer 5.0 swap. I used the 164 tooth/50oz flywheel as recommended and everything fits up great. Issue is I have vibration coming from the motor (In neutral/not in motion) when I rev the motor past 2k.

Motor mount and trans x-member bushing are new and everything is torqued to spec and solid. Motor barley moves when the throttle is bumped.

Does the harmonic balancer need to be changed to support the difference in weight between the old flex plate and the new flywheel? I found one for the F150 motor but the pulleys are different and the F150 pulley belt location looks further away from the engine.

What else could cause the new vibration?

Any help or advice is greatly appreciated! Have a great weekend!

Talked with the guys at Dampner Dudes and they recommended getting the new flywheel and pressure plate balanced together. Pulling the trans today and get the parts balanced tomorrow.

 

[DirtDonk]

Good luck. I hope that’s all it is.
As you found out, the explorer damper, that you are presumably using up front, is already the correct balance for the engine, obviously.
And neither the front damper, the flywheel, or the pressure plate should require balancing to avoid a vibration.
But balancing, especially with the pressure plate together, is still a good practice. So nothing wrong with doing the extra work to get rid of a vibration. If that’s the problem…

Vibrations are very annoying! Did you do other checks as well? Such as removing the serpentine belt to make sure it’s not a front accessory? Or check cylinders by doing a compression test or even the simple act of removing a spark plug wire from each cylinder in turn?

And make sure that whoever is doing the balancing can check that your flywheel is actually a 50 ounce fly wheel and not an mis-boxed 28.
I guess that’s not as likely in your case, since the vibration only starts after 2000 RPM. If it was truly the wrong flywheel imbalance, it should be vibrating just above idle and all the way up.
But getting mis-boxed parts these days, is an all too common experience.
So still worth verifying.

 

[Antsun]

Good luck. I hope that’s all it is.
As you found out, the explorer damper, that you are presumably using up front, is already the correct balance for the engine, obviously.
And neither the front damper, the flywheel, or the pressure plate should require balancing to avoid a vibration.
But balancing, especially with the pressure plate together, is still a good practice. So nothing wrong with doing the extra work to get rid of a vibration. If that’s the problem…

Vibrations are very annoying! Did you do other checks as well? Such as removing the serpentine belt to make sure it’s not a front accessory? Or check cylinders by doing a compression test or even the simple act of removing a spark plug wire from each cylinder in turn?

And make sure that whoever is doing the balancing can check that your flywheel is actually a 50 ounce fly wheel and not an mis-boxed 28.
I guess that’s not as likely in your case, since the vibration only starts after 2000 RPM. If it was truly the wrong flywheel imbalance, it should be vibrating just above idle and all the way up.
But getting mis-boxed parts these days, is an all too common experience.
So still worth verifying.

I did not think about pulling the serpentine belt…. I did put a new alternator and water pump on. I will try that first and then do a compression test as well. Those are way easier than pulling the trans!

Thanks DirtDonk!!

 

[Antsun]

Good luck. I hope that’s all it is.
As you found out, the explorer damper, that you are presumably using up front, is already the correct balance for the engine, obviously.
And neither the front damper, the flywheel, or the pressure plate should require balancing to avoid a vibration.
But balancing, especially with the pressure plate together, is still a good practice. So nothing wrong with doing the extra work to get rid of a vibration. If that’s the problem…

Vibrations are very annoying! Did you do other checks as well? Such as removing the serpentine belt to make sure it’s not a front accessory? Or check cylinders by doing a compression test or even the simple act of removing a spark plug wire from each cylinder in turn?

And make sure that whoever is doing the balancing can check that your flywheel is actually a 50 ounce fly wheel and not an mis-boxed 28.
I guess that’s not as likely in your case, since the vibration only starts after 2000 RPM. If it was truly the wrong flywheel imbalance, it should be vibrating just above idle and all the way up.
But getting mis-boxed parts these days, is an all too common experience.
So still worth verifying.

Alright, pulled the belt no change.

Between 120 and 130 on all cylinders and spark to each.

I am noticing vibration at idle but anything past 1600 is very noticeable.

I bought the flywheel from Wild Horses. The shady part is that when I called them to ask what manufacture the flywheel is before I bought it they said they use a few different ones. When I received the flywheel/clutch they had used a razor knife to remove all the manufacturers model number stickers (Luk ended up being the manufacturer). I think I will just buy a new one that I can verify is 50 oz, have that faced and balanced with the pressure plate.

Thanks for the input DirtDonk!!

I’ll keep this updated with any new info I find.

 

[73azbronco]

Make sure it’s firing on all 8

 

[DirtDonk]

Luk is one of our major suppliers for clutch and flywheel parts. We just can’t always keep enough on hand from one supplier so have to use multiples.
It’s not a secret, so not necessarily anything shady about removing the part number. Since we put our own part numbers on every part we sell, sometimes it makes sense.
I mean after all, even if we take it off the box, the part number, and manufacturers name, is usually still on the part itself.

And in their case, I doubt that the part was mis-boxed at the manufacturer level. And a defect would be low on the list too. But as with any manufacturer, not completely unheard of.
If it was mis-boxed afterwards, it would’ve only been as a returned part since we use their own box that it came in.
Is there a part number on the flywheel itself? With that we could easily verify if it’s correct.

Like I said earlier though, it’s not likely that it’s the wrong imbalance factor anyway. That would vibrate severely. Literally undrivable above about 1500 RPM.

While you’re checking things, look for anything else amiss. You’ve checked the front accessories, so that’s good. Now check to make sure no shifters are hitting the floor sheet-metal. No driver side cylinder head contacting with the firewall, no exhaust system parts rubbing on anything.
Things like that happen all the time when moving the engine around to replace things. And engine mounts and flywheel/clutch can often disrupt that.
What about the clutch? Sounds like this is a new installation, so I’m guessing the clutch is new as well? Maybe the clutch is what’s out of balance.
When I replaced my clutch 30+ years ago, I used the original flywheel and got a slight vibration that I’m sure wasn’t there before.
Was actually pretty small, and only noticeable above 2000 RPM or so. Was annoying but I never pulled it back apart to fix it.
Hmmm, sounds familiar…

So, nothing wrong with going either way. Have it checked and balanced with the clutch, or get a new one and have it balanced with the clutch.
Just in case there is a balance issue. But don’t ignore any of the new parts that are spinning.

Speaking of spinning…
Have you checked it with the clutch engaged and disengaged? When you rev it up and feel the vibration, does it change when you push in the clutch pedal?

More stuff to check before you pull it apart.

 

[Antsun]

Luk is one of our major suppliers for clutch and flywheel parts. We just can’t always keep enough on hand from one supplier so have to use multiples.
It’s not a secret, so not necessarily anything shady about removing the part number. Since we put our own part numbers on every part we sell, sometimes it makes sense.
I mean after all, even if we take it off the box, the part number, and manufacturers name, is usually still on the part itself.

And in their case, I doubt that the part was mis-boxed at the manufacturer level. And a defect would be low on the list too. But as with any manufacturer, not completely unheard of.
If it was mis-boxed afterwards, it would’ve only been as a returned part since we use their own box that it came in.
Is there a part number on the flywheel itself? With that we could easily verify if it’s correct.

Like I said earlier though, it’s not likely that it’s the wrong imbalance factor anyway. That would vibrate severely. Literally undrivable above about 1500 RPM.

While you’re checking things, look for anything else amiss. You’ve checked the front accessories, so that’s good. Now check to make sure no shifters are hitting the floor sheet-metal. No driver side cylinder head contacting with the firewall, no exhaust system parts rubbing on anything.
Things like that happen all the time when moving the engine around to replace things. And engine mounts and flywheel/clutch can often disrupt that.
What about the clutch? Sounds like this is a new installation, so I’m guessing the clutch is new as well? Maybe the clutch is what’s out of balance.
When I replaced my clutch 30+ years ago, I used the original flywheel and got a slight vibration that I’m sure wasn’t there before.
Was actually pretty small, and only noticeable above 2000 RPM or so. Was annoying but I never pulled it back apart to fix it.
Hmmm, sounds familiar…

So, nothing wrong with going either way. Have it checked and balanced with the clutch, or get a new one and have it balanced with the clutch.
Just in case there is a balance issue. But don’t ignore any of the new parts that are spinning.

Speaking of spinning…
Have you checked it with the clutch engaged and disengaged? When you rev it up and feel the vibration, does it change when you push in the clutch pedal?

More stuff to check before you pull it apart.

Thanks for all the pointer sir!

Clearances from motor to firewall are good. Trans/tcase not touching anything it shouldn’t. Exhaust is also not rubbing.

Just finished adjusting the slave and the clutch (new) works great. There is no difference in vibration with clutch in/out.

Sounds like I probably have the 50oz FW as I can get past 2k driving just fine.

I will pull the trans and flywheel and see if there is a model number. If it’s right I’ll have it balanced with the pressure plate. If it’s wrong there is a new one from Summit that will be here on Wednesday.

Thanks again DirtDonk! I’ll keep the thread posted when I find anything new.

 

[DirtDonk]

… Now where is that crossing fingers emoji when I really need it!

Was hoping that you could find something without going through the trouble of redoing what you’ve already done.
Wouldn’t be the first time of course. Most of us have gone through it at one time or another. But sharing It doesn’t make it any less frustrating!

 

[Antsun]

… Now where is that crossing fingers emoji when I really need it!

Was hoping that you could find something without going through the trouble of redoing what you’ve already done.
Wouldn’t be the first time of course. Most of us have gone through it at one time or another. But sharing It doesn’t make it any less frustrating!

Hahahah. Very true. I’ve pulled this entire drivetrain apart so many times it’s second nature… hahaha. Trans is out and the below is the only marking on the flywheel.

51701104 253 21344

I’ll work on cross referencing the part # tomorrow but will also compare to the new one when it arrives.

 

[ba123]

Make sure it’s firing on all 8

exactly what I was gonna say. your vibration might just be because you aren't.

while it's good practice to balance, you really shouldn't need to for this basic stuff.

are you sure you got the right imbalance flexplate and balancer

 

[Antsun]

exactly what I was gonna say. your vibration might just be because you aren't.

while it's good practice to balance, you really shouldn't need to for this basic stuff.

are you sure you got the right imbalance flexplate and balancer

Compression is good, spark at all plugs, fuel pressure at the rail, plugs not wet, no CEL, and it definitely gets up and goes without hesitation/starts right up.

The flywheel is what is currently in question as I don’t know if I was shipped the correct one. I didn’t think you had to balance anything but it never hurts.

The guy at Damper Dudes was pretty knowledgeable on this setup. Said the stock harmonic balancer was correct and the 50oz flywheel was also correct. He said he takes the old flex plate and balances the new flywheel to match any factory offset. Then puts on the pressure plate without the clutch and verifies that is balanced.

Too bad I’m not in CA…. There should be a few places in Denver that can do this.

 

[DirtDonk]

If it was earlier in the year, I’d say make it into a road trip!
Ok, so life ain’t that easy. But it’s always fun to think about it.

 

[Antsun]

Alright here’s the skinny for those following.

Casting on the flywheel is correct for part LUK LFW161 (164 tooth 50oz). I have called Schaeffler/LUK and the have confirmed this.

Found a guy locally to balance the flywheel/pressure plate using the OE flexplate as a reference.

Drop it off today and may have it fired back up by Wednesday.

Happy Monday!

 

[blade]

Did you check your harmonic balancer to make sure the outer ring isn't shifted out of palce?

 

[pcf_mark]

I had the wrong flexplate/ AT flywheel on my 5.0 and the vibration was like a rolling vibration. It was unique - not like a dead cylinder mis that was constant but as you revved in neutral it would be like a vibration of increasing magnitude rolled thought the truck. When you let off it would reverse dircetion almost. Really funky. Learned the C4 flexplate was not correct for a modern 5.0.

 

[Antsun]

Alright problem solved! Flywheel was in fact correct but horribly balanced by Luk. Bought another one from Summit and same issue.

Guy that balanced it was bewildered by the poor craftsmanship on this….

Anywho, it’s all back together and smooth as a Cadillac now!!!!

 

[bentendo]

Really glad you got this resolved. I swapped to a '96 Explorer 5.0 a few years back, and have been going crazy with the *exact* same issue. Not thrilled to pull my transmission, but this sure sounds like the fix. I replaced my harmonic balancer to try to fix mine, and it seemed to settle the vibrations down a little, but it's still there.