The Stovebolt Site Forums The Shop Area Driveline 52 3100 question

Hello.

I am new to this. I am the proud owner of an original 52 Chevy 3100 with just under 47,000 original miles. I have been driving it daily and absolutely love this truck. Here is the thing. I was pulling out of a parking space last night and as I proceeded forward I felt a large CLUNK from either the rear end or the transmission output shaft followed by the truck continuing under its own power for about 50 feet then as I turned left the truck locked up. All of the gears work fine but the rear end locked. The rear output pad is missing. My question is could this be caused by either a ring and pinion failure, or if the transmission/engine moved slightly out of alignment could it cause the drive line to "kink"? As I was driving it last night between gear changes it was making a lot of hard banging noises. My mechanic had told me that it is fine to drive it but just need to replace the mounting pad. Apologies in advance if this is an elementary question. Any help/advice would be appreciated.

(original 216 and 3 speed column shift)

Check your u joint directly behind the transmission output shaft. You will have to pull the bell cover back to get to the u joint. It gets lubricated from the transmission oil.

Welcome to the Stovebolt Page! There is a forum called the Welcome Center where you can introduce yourself and your truck.. Does your truck have the original torque-tube drive (enclosed driveshaft)? It is possible that you suffered a rear end failure, but more than likely it's a u-joint... What do you mean by rear output pad and mounting pad? Do you mean one of the rear bellhousing mounts? I'm going to guess you are still learning about these old Chevy trucks, so I will try to guide you to a place with more information.
48-51 Truck Shop Manual This link goes to the page in the shop manual that describes the engine mounts. That entire website is chocked full of old Chevy information. So make yourself acquainted with it. There is also info there about the u-joints, etc.
Could you post a picture of the mounting pad that is missing? On the left of this page are instruction for posting pictures in your post. Since you are new here your posts are monitored and you may have to make so many post before you have permission to post pics.
Good luck.

Thank you! I am new to forums as well as these old trucks. But yes, it does have the original torque tube drive shaft. I hadn't even thought about a u joint. I went worst case scenario immediately. And by mounting pad I mean where the rear output of the transmission rests on the cross member. That is completely missing (the rubber pad, not the cross member) and the rear engine mounts are both shot so there is a bit of movement. Thank you for the link to the shop manual. I will try to figure out the Welcome Center. Technology haha

Just a note: Photo restrictions have been lifted as far as newbies posting pictures. Follow the directions in the left margin of every page.

I don't really understand your problem exactly.

A couple years ago, I broke a rear axle, so even though the engine ran, and the transmission gears were there, and the truck would roll if pushed, the engine would not turn the rear wheels.

I don't suppose this is what you are describing?

I will attempt to add photos as soon as possible. Thanks!

I sure wouldn't listen to that mechanic & keep driving it. It sounds like you have a broken tooth on a spider gear in the rear end. You should pull the cover of the rear end & check it out. Locking up like that means something serious.
George

Boy I hope that's not the case. But if it is then so be it. This is a bit off topic, but would changing the rear gearing to maybe a 3.55 or something affect the drivabilty much? What I mean is this: I drive this truck a lot. My regular vehicle is a '17 RAM 2500 but I prefer the '52 and have been using it daily to and from work (round trip of almost 60 miles daily) and in stock form I cannot take it on the freeway. I also live where there are a lot of hills. I don't mind taking back roads but it would be nice to have the option. So my question is if i change the gearing would I be able to still get up hills (fairly steep, 2nd gear in current form) and have the option of an occasional 65 mph? I am not looking to change the transmission or anything. I apologize for my lack of experience in these matters. Thanks!

Answer to your gearing question is; if you are already using second gear to get up the hills you will be using first gear to get up the same hills with a lower numerical rear end. Mother.Trucker sells the 3.55 sets.

Good to know. Thanks!

I'm thinking that I'll stick with stock everything. I'm good with slow and cool

So here is the latest with my truck dilemma. On jack stands the rear tires spin. Checked the ring and pinion, all good. Checked the u joint. So far so good. Tomorrow I'll mess with the transmission. It's been grinding from 2 to 3 at any speed when shifting.

When you inspected the ring and pinion, did you also look closely at the spider gears - labeled in the attached image as pinion gear (not to be confused with the drive pinion gear) and side gears? By my experience with other rear ends, the spider gears are more likely to fail than the ring and pinion (usually due to a galled pin - labeled differential pinion gear shaft - from lack of lubrication, but they do break teeth, as well). If a gear tooth sheared and wedged in the differential gears, it might cause what you experienced as "lock up."

A similar thing can happen in the transmission. Many years ago, I bought a parts car from a friend that had a "locked" 3-speed manual. When I took the cover off, I could see a broken tooth on the second gear, and wiggling the yoke back and forth freed it up so that the broken tooth piece dropped out from between the gears. At that point the transmission would turn fine, but with the seriously broken gear tooth, it wasn't going to run for long....

Good luck with the continued diagnosis!

KING CONAN,

With all of the traffic on the 205, you can't get going very fast anyway. I know, I drove it for over 20 years. Good luck with your truck. Listen to what these guys have to say. They are a wealth of knowledge and experience.

Rugo

Rugo

The traffic on 205 has only gotten worse! But yes, these people are an absolute wealth of knowledge. So great to be able to just throw a post up and to be given such safe advice. Pretty rad

Hey drdoug
Thanks for your knowledge. With my truck because of the very low miles I'm thinking that seals have rotted over time and fluids have leaked. I went through the rear end today and nothing is broken or worn. But a solid excuse for a fluid change. The u joint has a bit of lateral play but no sloppiness vertically. I'm looking towards the transmission as it's been grinding with shifts. So many steps! Thanks again and I appreciate the help and insight