rear end calamity...67

[jeboblasto]

Hiyo, i am teaching myself now to fix my truck, one problem at at time, one might call me a youtube mechanic or something. I have a rear end issue, that i'm having problems finding online info on and was hoping for a lead at the very least on what to look for. any advice is hugely appreciated. My right rear wheel skids, or slides, drags, during low speed turns. It is likely doing it all of the time, but is very noticeable at low speed. I am going to be able to get after it soon ( money and space required ) and am wondering if my issue lies in the differential ( my thinking ) or somewhere else. I have a 12 bolt diff, and will be opening it up soon to get more info. It's probably stock like most of the truck. Can a locking or limited slip diff become stuck in a locked position? and if so, what is the cure? I would usually find this out with hours of googling etc, but i have been unable to make a lot of headway. If anybody is feeling generous i would appreciate even a slight nudge in the right direction. Cheers!

[Tx Firefighter]

A limited slip rearend can absolutely do that. The most common cause is fluid issues. A clutch type of differential requires a specific type of fluid, but often folks just substitute the wrong fluid and it leads to issues like you're having. The first thing to do would be to change the fluid and refill it with the proper fluid that is specified as having limited slip additive. Then, take the truck to a parking lot somewhere and slowly drive it in multiple circles in both directions to cycle the differential with the new fluid. That often frees them up.

[jeboblasto]

Thanks very much, i will do that this week. Cheers!

[Tx Firefighter]

Just to qualify my answer further, this is a real possibility with a limited slip rearend. If you have an open rearend, there's something more serious going on. Be sure and snap pictures when you get the cover off. Also, jack the wheels off the ground and spin the rearend around a bit and look up in there closely at the gears. If something is going south, you'd likely be able to spot it even without being very experienced in differentials. Chipped gears or blue bearings or metal chunks laying in the bottom are pretty obvious if you look closely.

[michael bustamante]

Tx is right on. Take the cover off and loo for chipped gears and shavings in the fluid. Keep us informed

[jeboblasto]

Hiyo,
No chips or worn gears in the diff, it looked pretty good. no metal in the bottom so i think i got to it in time. i'll try and put a pic up here. I got a new gasket, and used sealer/gasket maker on it and filled it up with appropriate lube and put the additive in first. I am selling the box off my truck, which is not bolted up so i'm going to wait until the weekend to drive and check if it's done the trick. Not leaking though, so i'm pretty happy and optimistic.

thanks for the advice, and i'm hoping that i don't find out it's not limited slip or something wierd from this pic. cheers, thanks again.

[PGSigns]

Not sure if it the angle and lighting but it looks like some signs of heat in that thing. Plus it also looks like the pinion has been rubbing on the carrier at some time. I would look at it further. Also rotate it 90 degrees from where it is now and take a picture of the spider gears. This will tell us if it is a posi or not. If not then you have another issue. I think you have another issue.
Jimmy

[BR3W CITY]

I'd get some lash gauges and look at it that way, if you can.

Usually tho, from my 5-6 personal experiences with similar problems; its the fluid.

I've had this happen on 3 s10/blazer/bravada's, my personal 66 with a 72 rear end, and on our liftgate truck.

Usually, assuming the truck is LSD, its just a matter of changing the fluid to some GOOD stuff with the friction modifier built in....OR getting a decent "regular" gear oil, and add a high-quality Friction Modifier. The name brands all make them, but I've also found the Napa (valvoline) stuff to be just fine for the money. The effect is instant. The first right turn you take, you will no longer feel the inside wheel trying to buck/clank.

I've heard that putting that modifier in a non LSD vehicle can be less than ideal, but I don't know if it has the same "instant" change.

[Tx Firefighter]

Those gouges around the carrier look to be a problem. It looks like the pinion gear has pushed backward and rubbed the carrier as it turned.

[BR3W CITY]

i thought that was a reflection.

[Tx Firefighter]

Originally Posted by BR3W CITY

i thought that was a reflection.

You may be right. I sure hope so.

[jeboblasto]

i was using my camera on my phone, which is poor quality. I'm hoping that's all it is, will do a test run asap. just sold the bed/box so i am doing a bit of other maintenance first. thank you for all the comments, i will post once i do a rip up the street and back and see result or lack thereof. cheers!

[jeboblasto]

took the truck for a quick turn around on my street and it seems like the dragging tire situation is gone away! Super happy about that, thank you very much for the sage advice, i do think my photo was just poor lighting/camera, and i'm glad it wasn't something more serious. Cheers!

[BR3W CITY]

Originally Posted by jeboblasto

took the truck for a quick turn around on my street and it seems like the dragging tire situation is gone away! Super happy about that, thank you very much for the sage advice, i do think my photo was just poor lighting/camera, and i'm glad it wasn't something more serious. Cheers!

Anti-climactic! Did you make any changes? I'm not sure how just letting her sit in the driveway solved the problem....but I guess I can't complain with the KISS principal!

[jeboblasto]

opened it up, drained old lubricant, new gasket, sealed it up again, added proper oil + limited slip additive. Yes finally took it for a short rip and it definitely is fixed, i'm not sure if i mentioned the solution part. Oops! Haven't been driving it due to no bumper/tail lights but bought my tail lights/reverse lights today and will get them rigged up soon. Also a swap/parts meet this coming weekend so i hope to have the bumper on asap. cheers.