Unknown Noise

[AZTrooper]

So I noticed this last weekend after I took the trooper out of 4 wheel drive, whenever I accelerate I hear this sound now that seems to be coming from the front of the vehicle. It generally starts at about 3000rpm and continues to get louder with higher RPMs. It almost sounds like I have a supercharger. It doesn't grind, it doesn't squeak, it almost sounds to me like it's coming from the tranny. Like the 4low didn't disengage all the way or something. I know this is pretty vague info, but any ideas would be greatly appreciated. Thanks in advance.

[crawler#976]

I'd start by checking your skid plates, brake rotor dust shields, or anything else that may have been bent on Smilely Rock...

[AZTrooper]

Thanks!! I'll have to check the skid plates. It's not going to be the brake rotor shields cuz it will do it when I'm in park. I need someone to step on the gas to rev it up while I'm under the trooper.

[AZTrooper]

Hey Scott!!!! Where did you say I could pick up one of those automatic tire deflaters?? I want to get one. Also Scott, I want to install an air compressor small enough to fit in the engine compartment. Which compressor would you get?

[Scott Brady]

You can get them from Extreme Outback Products (http://www.extremeoutback.com/)

If you want, you can buy my Trooper compressor set-up. I would sell it for $200

It should be a direct bolt in: http://www.expeditionswest.com/equipment/trooper/compressor/compressor.html

(just check to make sure your engine compartment is configured the same)

[crawler#976]

if it's happening in park, I'd suspect the flex plate spash/dust cover if it's an automatic.

[bigreen505]

So I noticed this last weekend after I took the trooper out of 4 wheel drive, whenever I accelerate I hear this sound now that seems to be coming from the front of the vehicle. It generally starts at about 3000rpm and continues to get louder with higher RPMs. It almost sounds like I have a supercharger. It doesn't grind, it doesn't squeak, it almost sounds to me like it's coming from the tranny. Like the 4low didn't disengage all the way or something. I know this is pretty vague info, but any ideas would be greatly appreciated. Thanks in advance.

My gut reaction is to make sure TOD is turned off (i.e. engage it, drive a few feet, disengage). Then take the truck to a car wash and get all the dust out. Mine does something slightly similar to what you describe but I hear more of a growl/resonation at lowish RPM and have just written it off as a Trooper sound.

[datrupr]

just written it off as a Trooper sound.


Hey, the "Trooper Sounds" are all part of what make a Trooper a Trooper. They also add to the character. However, that said, I would have to agree with Mark on this one. Mine has never made a noise like that.

[AZTrooper]

You can get them from Extreme Outback Products (http://www.extremeoutback.com/)

If you want, you can buy my Trooper compressor set-up. I would sell it for $200

It should be a direct bolt in: http://www.expeditionswest.com/equipment/trooper/compressor/compressor.html

(just check to make sure your engine compartment is configured the same)

From the what I can see, it looks like your compressor unit should be able to fit in the same spot in my engine bay. I'll buy it from you!!! Will you part with all the air lines and such that you have compiled for your trooper application? I plan on running Smiley Rock again sometime in the next month or so with a few guys from work. So maybe I could give you a few days notice so we could make a trade. Whaddaya say?

[Scott Brady]

So maybe I could give you a few days notice so we could make a trade. Whaddaya say?

Just shoot me an email. I am around this Sunday and most of next week.

You will get everything. All of the hoses, wiring, bracket, chuck, etc.

[AZTrooper]

Hey Scott- you told me that someone out there makes a replacement transfer case with lower gearing. Can you give me any info on that? Thanks!!!

[AZTrooper]

I found the problem that has been making that whining sound!! Sometime last weekend while running the trail I managed to put a nice 8 inch dent/scrape in the pan on the bottom of my transmission. Yeah... I'm starving my tranny for fluid and that's why I'm getting the whining sound. I have to take the pan off this weekend and bang out the huge dent and replace the tranny fluid. YIPPEE!!!

[crawler#976]

kinda figures it had to be trail damage...glad you foung it!

[AZTrooper]

I suppose I'm kinda glad that it's trail damage. Gives me an idea of what to look out for in the future. Maybe I should fabricate some sort of skid plate to protect it in the future. What do you guys think?

[Scott Brady]

I did that once too... smaller dent though.

The Transfer case gears are from Tera, but I just remembered that you have TOD, so I am not sure if there are replacements for that (dont think so).

[bigreen505]

Nope, been down that road already. If it makes you feel any better, TOD buys you a 2.48:1 low compared with the 2:1 low in the non-TOD models, giving you a 30.5:1 crawl -- probably a pretty good match for mild trails.

[AZTrooper]

So after I talked to a local transmission man about my 4L30-E tranny, he told me it's probably about time for a rebuild anyway. The trooper has 164,000 miles on the stock tranny. Maybe I'll just get it overhauled. The dent in the pan is only about 1/2" deep and 6-8 inches long. I'm wondering how deep a dent has to be to bust a solenoid or something. Any thoughts?

[crawler#976]

If you plan on continuing to wheel trails in the Smilely Rock range, then a oil pan/tranny skid would be a good idea. Lots of options for building your own - but I wouldn't go less than 1/8" steel or 3/8" nylon sheet backed up by some tubing.

Also, if you don't get a skid, carring a spill kit should be mandatory.

And, I'd recommend getting some of the oil (hydrocarbon) activated epoxy to use for a pan patch if needed. We've made do with the plastic from a milk jug and a ton of duct tape by cleaning everything with brake parts cleaner first, but it's not a real good setup. I'vegot a buddy who used the epoxy to fix an oil pan 4 years ago, and it's still there...

[Scott Brady]

So after I talked to a local transmission man about my 4L30-E tranny, he told me it's probably about time for a rebuild anyway. The trooper has 164,000 miles on the stock tranny. Maybe I'll just get it overhauled. The dent in the pan is only about 1/2" deep and 6-8 inches long. I'm wondering how deep a dent has to be to bust a solenoid or something. Any thoughts?

Fix the pan would be my recommendation.

[AZTrooper]

Taking the pan off and pounding out the dent is what I would like to do. Does anyone know if there is anything breakable within the half inch that it dented? The pan is about 3 inches deep. If there's nothing between the bottom of the pan and where it bolts to the transmission, I just might leave it alone and fabricate a removeable skid plate.

[Scott Brady]

Your best bet is to remove the pan and inspect the valve body for damage. Easy job and you can change the fluid at the same time. I would replace the pan as opposed to hammering it out.

[AZTrooper]

So the valve body is within an inch and a half from the bottom of the pan huh?!? Kinda seems like not such a good design. Oh well... I'll have to unbolt the cross beam so that I can get to the bolts.

[Scott Brady]

So the valve body is within an inch and a half from the bottom of the pan huh?!? Kinda seems like not such a good design. Oh well... I'll have to unbolt the cross beam so that I can get to the bolts.

All automatics for passenger vehicles are designed that way :) You just need a skid plate :box:

[AZTrooper]

So I have an appointment for a local tranny shop to check things out. Tomorrow a buddy and I are gonna make a few custom skid plates for the trooper.

Hey Scott, I have money for the air compressor. How do you propose I go about getting it?

[AZTrooper]

So... $86 later, it turns out that the noise was coming from the pump in the tranny starving for fluid. The metal container that holds the filter about 1/2" from the bottom of the pan got crunched a little and was pinching the filter itself. This was restricting flow for the pump. So overall, not a bad diagnosis. They replaced the filter and changed fluid. Since there was a lot of metal particles on the magnet, he suggests I rebuild the tranny. I told him it shifts beautifully and I wasn't interested in a $2,000 rebuild. But for now all is well and I'm glad it turned out to be a small problem.

[AZTrooper]

So I have an appointment for a local tranny shop to check things out. Tomorrow a buddy and I are gonna make a few custom skid plates for the trooper.

Hey Scott, I have money for the air compressor. How do you propose I go about getting it?

Scott, I still want that air compressor. How can we make the transaction? I bought one of those fancy deflators too!!