Drivetrain Whining

[1973Guppie]

Finally got the cruiser on the road, will post pics soon. I noticed when I was driving it last night that there is a definitive whining sound coming from the drivetrain. When the drivetrain is engaged (ie: throttle) the whining is louder and when I let off the gas it settles down some. I am running a V8 vortec to older lower geared NV4500 to a 3spd TC from a 73 FJ40. Truck is a 73 FJ40. It has been so long since I drove it (2 years) I can't remember if it used to be this loud or not. I do have a soft top and hard doors on it now so this may be part of it as it probably keeps the sound in the cab more, never ran a top before. I don't really care about the noise, if this is how it is supposed to sound, no problem I will live with it but want to make sure I am not having issues with any part of the dtrain. Axles, TC, Tranny, etc all have fresh oil and have been topped off. Was wondering if anyone else with this setup gets this type of noise when under throttle. wwwweeeeeeeeeeeeeeeeeeeeeeee



Noah

 

[TJDIV]

I'd put almost everything I own on your Transfer Case. The only reason I say this; I had the exact same problem (when you let off the gas, for obvious reasons, the gears aren't engaged as hard as they are moving your rig).

Anyway, I thought it was the transmission, so I just went ahead and ordered a conversion to a 700R4 without even looking at anything, because I KNEW something was f*cked. Long story short. I went through a LOT of s*** and some cash to do a massive job (wound up doing axles and everything); and it f*cking just so happens that I could've swapped my case out, kept my 3 Speed Manual and been fine for 5 or 6 more years.

I am happy with the conversion. Just bitter-sweet (uh..yeah...you think?)

Open up your case, better yet, drain it and look for metal. Then clean it out and fill it up with oil, that'll kill the noise a little for now. If that's not it, look at your transmission. I don't know much about the NV4500, never f*cked with one, but a lot of the guys have.

IV

 

[1973Guppie]

Both the tranny and TC have been rebuilt. I have heard that the older 3spd non split TC's are much louder? Have never run an nv4500 till now but have also heard that the older style NV's are louder as well.

Noah

 

[crucible]

My 83 FJ60 whines like an old school bus, and is not very pleasant to listen to. (If anything, even after all the blood/sweat/tears of owning this beast, it will be this that will make me get rid of it eventually.) Admittedly, I may be a bit sensitive to it now, and relatively-speaking, it might not be too bad compared to others but.......

I'm fairly certain it's the t/c as well, and have changed the oil etc., too. As it seems to work just fine despite the noise it generates, I cannot justify a rebuild at this time on it either; I've spent too damn much on my cruiser as it is for things that haven't worked. That being said, I did find something that quieted things some: Lucas oil.

Cruc, whos sounds like he hates his cruiser, but really does only some of the time, Cruc

 

[1973Guppie]

EXACTLY! Like an old school bus! almost like a whirrrrrr and gets louder as I go faster. Probably just the way it is, afterall I have been driving an expedition for the last year and a half and probably have become soft.



Noah

 

[Degnol]

I'll bet it will quiet down a little after you drive it for a while. The 3-speed TC's are notoriously whiney. I got some relief by putting down some thick soft rubber floormats that I had in my 'Burb, you know the kind that look like a waffle. Just cut 'em to fit and it way cut down on the resonance from the floorboard sheetmetal.
GL
Are you married? If so, you should be accustomed to whining, and if you're planning on getting married, it is great training.
Ed

 

[1973Guppie]

why do you think it will quiet down after awhile? Does this have to do with the drivetrain breaking in after awhile.

almost....I am engaged, yeah, get lots of whining...Babe, why is there cruiser parts in the downstairs kitchen, bathroom and bolts in the pots

damn woman always nagging me!

I am a lucky man...

8)

 

[Iron_Pig]

Hey Guppie,I'm going through a similar thing. I got the rig from my brother and it took me 2 years to build the motor and tub. Then when I hit the road it whined like a skinned cat. I asked my brother about it and he said it didn't whine when the engine blew. I talked to "wrenches" and posted a similar question on this board.
STEP 1: Change the tranny & transfer case fluid. That cut the noise to still there,but bearable.Before I did that I couldn't carry on a conversation because of the whining noise!
Step 2: Keep driving it. When a gearbox sets the bearings will get surface rust on them and it will quiet down once it wears off and the bearings,gears get lubed again with some HOT lube.
Step 3: Suspect the transfer case FIRST.
Step 4: Go read my posted topic on this same subject and see if I missed anything.
My FJ40 has some noise still,but I don't think these rigs were ever QUITE :-\

 

[1973Guppie]

thanks for the feedback, I will do a search. All the fluids are brand new so I don't know if changing them would make a diff, maybe stuff just needs to break in. I have some rubber matting on all the floorboards, but do have a plastic tranny cover that has been lined with dynamat. This may be letting in more noise than metal would have let in? anyhow, thanks.

Noah

 

[TJDIV]

Yeah, mine may have been a little different. When I pulled the plug on my T-case I had enough silver based liquid to paint a car. Not too mention about 4 pounds of metal chunks.

 

[1973Guppie]

I think I may of figured things out. Drove all day around San Diego today, about 3 hrs. Ran great, hand on the TC and tranny and they were warm but by no means hot or overheated. I think it is a combo of using a plastic tranny hump and I did forget that when I installed the Tranny hump I had to cut off a small area from the plastic because I had the TC tucked up so far that the Tcase saver plate that I am running comes up above the stock level height of the floorboards. Only a small area, probably 1 inch wide and 3 inches long but I could see it letting in ALOT of noise. I did my best to cover the hole with some dynamat and the rubber floor matting from CCOT I have. Either way, no biggie as I can deal with the noise, just as long as everything in the dtrain is running correctly, which now I think it is. Just have to turn the Jimmy Buffett up a little louder now. Thanks for all with the help. I will post pics soon of the finished product.

Noah

 

[beanz2]

Noah,

The older NV4500 has a loud 3rd gear, but does the noise not vary between the gears? In my experience when I went to an NV4500, the rear driveline angle got a little too steep as the tranny itself is really long and the rear pinion was angled up for a much shorter SM420 that the NV replaced. My driveline noise was only there when I was letting go of the gas to coast. If you are running a CV driveshaft joint in the back, check to see if your pinion is still pointed up at your t-case output. If you aren't running a CV joint, check the U-joints aren't binding. HTH,

Dave

 

[1973Guppie]

Dave,

I start off on the street in 2nd gear, 2nd doesn't wine too bad but 3rd /4th / 5th do. I am running a CV joint in back but the dshaft is a little short. I need to send it back to high angle driveline to get it redone as the slip is pulled out about 2 inches, I wanted about an inch of compression but ended up with 2+, not sure if this is a factor. Rear pinion is angled up to the TC. As I mentioned above I think most of the issue is with the fact I am running a plastic tranny cover and had to trim it to fit the TC.

thanks,

Noah