demonte1997

I threw up a post about my truck and the awful noise it is making on the front end. http://www.silveradoss.com/forums/topic/83493-front-end-thunking-sound-while-under-load-please-help/ Wondering if anyone lives up my way that might have a minute to take a listen. It's really something that probably has to be seen/heard... without that I'll likely just end up throwing parts at it (well... already have with little success). I'm leaning heavy towards transfer case. At which point I may just try to get a spare from the JY and rebuild it myself. Already done u-joints and no change in sound. Might be hubs but I'm doubtful. If not that, even if someone can recommend a shop in CT that does decent work and who is reliable. I am very weary of dealerships... Some are fantastic but most are not. Most places by me don't have the slightest clue on what to do with an AWD truck. Thanks guys

Front and rear u-joints replaced first as I was hoping that was the issue. Nothing changed after so I'm afraid the originals weren't causing the noise. Good to hear that it shouldn't be the front diff. I'm still leaning towards the transfer case. The Harbor Freight bore scope sounds like a great idea. Might be able to see what's going on up there. I'm kinda stuck with the Timkens as I bought them two months ago and don't see any way I'd be able to replace them. Not sure why I had a brain fart and forgot about Moog. I've used their tie rod ends and lower control arms on w-bodies with great success. :/ Is anyone from New England on this board? I'd be curious if someone with a higher mileage truck could give it a listen and lmk what they think. Very much appreciate the info and time from you guys. As always.

I know sounds are difficult to diagnose over the net but was hoping someone can help point me in the right direction here. It is a rhythmic thunking sound that starts around 10mph (when truck shifts into 2nd) and continues all the way up until about 45mph. It goes quicker with speed and I can feel it in the floor/pedal/steering wheel slightly. It only happens when I'm on the gas. As said, it goes away at higher speeds. It also seems to go away if the rpms are high enough (ie: if I put load on the system and the rpms are at 1500, I get more thunking than if the rpms are past 2,000). The sound is similar to what a locomotive sounds like as it winds up and gathers speed. :/ I'm fearing the worst - transfer case or front diff. Some people have said it could be wheel bearings and I have a set of Timkens to put on but I'm pretty doubtful. Others have said it might be missing teeth in the front diff. Even others saying possibly stretched chain in transfer case.. Truck has high miles so I'm sure the driveline is worn.. a lot. I replaced the oil in the diff and it looked fine. Also changed out the fluid in the transfer case... not that it will fix either. 2002 Sierra Denali AWD with 171,000 miles on it. If anyone lives in New England, I'd be happy to drive out to them and let them take this thing for a drive.

Found a set of Falkens for a decent price from Discount Tire Direct. Will probably go with them. Thanks guys. As always, much appreciated.

Took your advice into consideration and would like to get 305/50/20 tires for the 20" wheels I have coming. Problem is that is seems like an expensive tire. I have seen better deals on tires for 22" wheels. Any hints on where to go and what tire is a good bargain? Walmart? Tirerack? Local?

Gorgeous truck

Welcome! Nice to have more CT peeps on the forum. Can't believe the previous owner let such a nice truck get this way but glad you are there to get it back to where it should be.

Thanks! Corsa tip huh? I'm interested. You have a link to it? I looked around for exhaust tips but didn't find anything nice. My buddy has an 03 that he'd like to get a tip for too.

Saw this one a while back but it's still funny as hell. hahahaha

Great info. Thanks guys, much appreciated! Couple pics of the truck. Will probably go with the silver rims with machined lip. Post pics when I get them.

What size tire do you recommend? I'm getting different answers. Some say 275/55/20. Others say 285/50/20. Not sure I care either way but would like the best fit. Truck isn't lowered so it's going to have a stupid amount of wheel gap (that's fine with me). Any advice is appreciated.

That's fantastic news. I had no idea the prior owner was an upstanding member here on the forums. Talk about a great way to handle it. Kudos to the seller to help split the cost on the cat. Really glad it was just a bad cat. In my limited mechanical experience, I've never heard one get that loud. Definitely take that over something more expensive. Enjoy the truck! Sounds like it was well cared for.

I dunno... that sounds really bad. Not one for jumping to conclusions, but it sounds like rod knock. Keep us posted. Hoping for the best. Seems coincidental that this happened right after you bought the truck, but that might be my legal background talking.

I have a few other GM online parts suppliers that I've used recently with better success than GMPD. If you want me to give their names, LMK. GMPD wants way too much for shipping and their order processing takes a long time (as you've seen).

After much digging and contemplating, here is what I came up with. It might not be the best decision but it would allow me the least amount of headaches. I had a few options come to mind after consulting techs about it and research: 1. Get original driveshaft repaired: I called around and no shops will repair an aluminum driveshaft. This was the consensus from 8 different shops in the area as well as ones in TX and western NY. All of which are heavy duty shops that work in this specific area. They asked what length it was and when I said it was ~70", they said making one out of steel would be a bad idea between strain on the driveline parts and possible issues with balancing and flex (aluminum can, steel does not as well). 2. Get used driveshaft and hope it doesn't have any balance issues. I found two that were within a half hour of me. One was supposed to be "A" grade. This is tough. They wanted $270 for the thing and I had no way of knowing if the balance was okay or if I'd be chasing new shimmy and vibration issues upon install. Also don't know how many miles were on it originally and/or why the truck was parted out. 3. Get aftermarket driveshaft. No aftermarket companies make anything comparable. In fact, companies that specialize in making aluminum shafts will not make one that's compatible. 4. Get OEM driveshaft from GM. OEM PN: 15165398 (i have it memorized) This is the only way you can get a new one. It is made by Spicer and even though their number is on the tag (Spicer PN: 923419-1610M) it is not available for aftermarket sale to the public due to licensing by GM (specifically and originally made for OEM use by GM so GM order only). I didn't want to take any chances, so I spent $550/shipped on a brand new OEM unit from a GM warehouse online. It should arrive in a few days. This seems like the only option if you don't want any potential headaches. The GM PN includes front slip yoke and Spicer u-joints. Thanks for the suggestions. Much appreciated. I'm not positive, but I think the Denali driveshaft is different from that of the SSS. Odd.. but make sure to cross reference PNs I listed above in case they aren't correct for your application. BE NICE TO YOUR DRIVESHAFTS!

Thanks for the reply. This is the only forum that I've been able to get info about it from. I see a Cardone 61" shaft PN 65-9528 that Amazon says will fit my truck. I don't trust Amazon much. The Cardone shaft looks way skinnier than the Spicer unit. Not sure if that would be an issue. Any additional info is appreciated. I'm a little weary of buying a used unit out of a truck from a JY. My old shaft was in really bad shape where the u-joints go in. The ridge where the e-clip holds the cap in was so corroded, it wouldn't hold the clip and it ultimately gave from the pressure and broke.

This is for my 2002 Sierra Denali. I'm not positive but was hoping my part would be the same as a Silverado SS. As it stands, I can't find much online. Google lists a Cardone part for the Denali but it is only 43". I think that would be for a regular cab. That's funny because the Denali only comes in extended cab... I also see one listed at 61" but it does not come up as being compatible for my truck. The other option is getting the Spicer factory shaft that would be big money (Cheapest I could find was $590/shipped). The Cardone shaft is closer to $300, is also made of aluminum and a remanufactured unit that comes with the u-joints already installed. This would be ideal if I could match up the correct part number. As an added bonus, my company has most sites blocked so I can't really even search on my lunch break for it (not that I blame them... but it doesn't help me out). Any help is greatly appreciated. I can't have the truck down for too long and would just like to get the ball rolling by ordering the replacement. Thanks guys! -Rick

I'm in Orange. You make a good point and I've been debating on doing that. Usually I like to have the parts lined up for a job like this but taking the joints out and matching them up at the parts store might be the best bet.

Hey Guys, First off, thank you for having me on your forums. I picked up a 2002 SD a couple months ago. Wanted that or a Silverado SS but couldn't find an SS that was affordable in my area so went the Denali route. I'd like to replace the u-joints on my truck as I think they are shot, especially the front. I'm trying to find replacements but the research is giving me mixed answers about what brand/parts fit. Now this is a stretch, but I was hoping the SS might share driveline components with my truck since they are both AWD. Mine is 4.10 gearing, which I think some if not all of the SS had (not sure if that matters). That said, does anyone know what part numbers I could use to replace the front and rear u-joints on my truck?? Any help is much appreciated. I look forward to participating on these forums as I'm sure there are some good threads related to performance as well. Pic of the truck. Thanks guys.