Author Topic: TCase Rattle (Read 4733 times)

MiniSimp · « **on:** Mar 12, 2007, 06:36:57 AM »

Extra smileys added in for my current depression.

Ok, so driving home last night I hear this small metallic rattle which "sounds" like it is coming from my rear transfer case.

Symptoms:

Simpson built duals MC08-R10 both fully rebuilt to spec

Does not rattle on acceleration

Does not rattle on engine braking

Does rattle when coasting

When rattling, will do it at any speed 5mph-75mph

Driveshafts apear to be in phase

Tires were newly balanced 33's

No death wobble

Front caster 4* back from stock (but always has been)

Not sure what else I can tell you...

As long as there is pressure on the shafts, no rattle.

My father-n-law is thinking maybe a bearing

I'm really not sure. Could just be a bolt under my seat.

The sound is like 2 pieces of 1/64" sheet metal vibrating together (if you can picture that) a very "tinny" noise, but kinda loud.

MiniSimp · « **Reply #1 on:** Mar 12, 2007, 09:17:10 AM »

Hottrod81 · « **Reply #2 on:** Mar 12, 2007, 09:59:18 AM »

Check your left front motor mount. It could be broken. That is what happened to mine when it made that exact same noise. I would have never known that without talking with Marlin.

MiniSimp · « **Reply #3 on:** Mar 12, 2007, 10:00:56 AM »

Will do, thanks.

BigMike · « **Reply #4 on:** Mar 12, 2007, 10:49:24 AM »

I was going to say the same thing: Motor or t/case mounts

Hyena · « **Reply #5 on:** Mar 12, 2007, 11:01:02 AM »

mine did that for awhile after i installed my duals, and it did it for awhile. then the noise just went away one day.

yotabj · « **Reply #6 on:** Mar 12, 2007, 01:04:17 PM »

Could be driveline angle,Mine does the same thing...It only does it on coasting..I noticed the problem right after I lifted my truck.Since then I lowered my truck 1 inch and rotated my rear axle.It solved my problem,several of the truck i ride with does the same thing.I believe it's the angle of your driveline and the sound is traveling to the t case .maybe i was some help

MiniSimp · « **Reply #7 on:** Mar 12, 2007, 01:34:06 PM »

Quote from: yotabj on Mar 12, 2007, 01:04:17 PM

Could be driveline angle,Mine does the same thing...It only does it on coasting..I noticed the problem right after I lifted my truck.Since then I lowered my truck 1 inch and rotated my rear axle.It solved my problem,several of the truck i ride with does the same thing.I believe it's the angle of your driveline and the sound is traveling to the t case .maybe i was some help

Also possible, I have added in 2 leafs from a 4" leaf pack to level my rear.

Cheesemaker · « **Reply #8 on:** Mar 12, 2007, 02:00:05 PM »

Did it do it before the tire balance? Try a different set of tires that isn't bb'd balanced? I would definitely check all the mounts. I know that 4THEWKN had a motor mount that was just rubbing at the right rpm's and it produced this very tinny sound!

MiniSimp · « **Reply #9 on:** Mar 12, 2007, 05:23:27 PM »

DS motor mount, I can't tell
Pinion angle
Transfer case waterfall leak

Hottrod81 · « **Reply #10 on:** Mar 12, 2007, 05:41:06 PM »

You can't if the motor mount is broken just by looking. Have somebody turn over the engine while you watch the motor mount to see if there is excessive movement.

BigMike · « **Reply #11 on:** Mar 12, 2007, 08:54:09 PM »

Yup, with the engine off, put the truck into double low range first gear and leave it in gear, then open the bonnett :talking: and rock the rig back and forth while watching the motor mount.

BTW, you added two leafs? I have removed THREE leafs from each side of my 4" rears!

MiniSimp · « **Reply #12 on:** Mar 12, 2007, 09:10:53 PM »

Quote from: BigMike on Mar 12, 2007, 08:54:09 PM

BTW, you added two leafs? I have removed THREE leafs from each side of my 4" rears!

Yeah, added 2 leafs to level it out, I'm hoping they break in after the hollister run, just gotta work it hard, if they don't I'll pull one.

MrsMiniSimp · « **Reply #13 on:** Mar 14, 2007, 05:03:56 PM »

Just a thought, but, the 2 leafs I added raised the rear about 3"
Could that in any way throw off my driveshaft angles?
I've got a protractor, so I'll go check them....

BLACKDOG · « **Reply #14 on:** Mar 14, 2007, 05:06:37 PM »

Quote from: MrsMiniSimp on Mar 14, 2007, 05:03:56 PM

Just a thought, but, the 2 leafs I added raised the rear about 3"
Could that in any way throw off my driveshaft angles?
I've got a protractor, so I'll go check them....

Man, first oldyeller, now Mrsmini is workin on your junk for you?

when're you gonna work on your own stuff?

MiniSimp · « **Reply #15 on:** Mar 14, 2007, 05:07:24 PM »

Yeah, oops, wife was signed in again. I've really got to learn to check that.

MiniSimp · « **Reply #16 on:** Mar 14, 2007, 06:14:20 PM »

Here are my driveline angles, could this be the problem?

1. TCase flange - 5*
2. Shaft - 21*
3. Pinion - 9*
4. Whole truck - 0*

MiniSimp · « **Reply #17 on:** Mar 15, 2007, 06:25:55 AM »

Bueller?......Bueller?.....

All_Set · « **Reply #18 on:** Mar 16, 2007, 11:37:24 AM »

Feel like doing some reading??

http://www.4crawler.com/4x4/CheapTricks/Driveline-101.shtml

Can't find it now, but there used to be a link from 4crawler to a site that broke down the angles of a dline for a dummy like me.

From what I remember, with a single u-joint drive line, the angle needs to be within 2-4 degrees of each other. If not, you *can* get vibrations.

edit: Found it.

http://www.geocities.com/benmlee/u-joint.htm

MiniSimp · « **Reply #19 on:** Mar 16, 2007, 11:57:36 AM »

Oops, forgot to update this.

I called Jess at High Angle Driveline and he said I need to go with a Double Cardan Driveshaft in the rear and rotate my pinion so it points directly at the transfer case.

All_Set · « **Reply #20 on:** Mar 16, 2007, 12:38:17 PM »

What wall thickness and what cardan is he going to set you up with?

Make sure to put up some pics when you get it!

MiniSimp · « **Reply #21 on:** Mar 16, 2007, 02:55:49 PM »

Sorry, no bling.
I'm going to find a stock front shaft.

MiniSimp [OP]

MiniSimp [OP]

MiniSimp [OP]

MiniSimp [OP]

MiniSimp [OP]

MiniSimp [OP]

MiniSimp [OP]

MiniSimp [OP]

MiniSimp [OP]

MiniSimp [OP]

Related Topics