The Stovebolt Site Forums The Shop Area Driveline Truck shakes big time starting out

Hi all, I am a new owner of a 58 3600. As I mentioned when I joind, I am no mechanic by any stretch of the imagination, but very determined to get this old original beauty rolling as it should. It drives great and everything on it works. It has apparently had a rebuilt motor and Tranny. Here is my problem. First gear is very low so I was told to start out in second which I have been doing. but sometimes the truck shakes so much I almost launched my 16 year old son out the front window (literally). He has observed that it happens more often when I am starting out on a turn. At first I assumed it was my lousy clutch foot but not so sure now. I do have a 1" play in the peddle and I seem to have an oil leak coming from a pan or cover where the engine and trany meet. I have not taken this pan off yet. Any help would be most appreciated. Thanks Rick

I'd check the motor mounts

Rick - there should be some free travel in the pedal, that's part of adjusting the clutch/throwout action - take the lower bellhousing pan off and see if the clutch disc isn't quite oily from a leaking rear main seal, which will result in a grabby clutch - also check engine mounts on all 4 corners for rotten rubber or looseness

Bill

Hi Guys thanks for the quick response. Just ran out and checked the motor mounts. They seem to be new on the front and in very good shape on the back. There does seem to be oil around the pan. I can take that pan off later this week but not realy sure what I am looking for in there other than oil.
Thanks Rick

If there's oil on the clutch making 'er shake, start in first, you may find that helps as you don't slip the clutch as much.

Also, does the 3/4 ton have a carrier bearing? If the driveshaft can jump up and down, it'll shake too. This happens on 1-tons, when the rubber ring that holds the carrier is worn/missing. I've never been under a 3/4 ton before.

What exacly is a carrier bearing. I'm gonna have to look that one up in th manual

I don't know if 3/4 tons have that animal. In 1-Tons, there are two driveshafts, with a bearing in a hanger between them.

Again, I don't know if 3/4 tons have this, as I've never been under one, and don't have the manual in front of me.

I'll probably look like an idiot in a minute, when someone says something contrary!

I had a 49 Ford...yes I know...that would shake like that and it turned out to be the king pins. Just my two cents.

My 49 3/4T has the carrier bearing, so I would guess the 58 will as well. Behind the transmission will be a short drive shaft with its rear end held in a bearing mounted to a frame cross member. There will be a u-joint, then the longer drive shaft to the rear axle. If the bearing or its rubber mount is weal, it could cause jumpy starts, but I would think an oily or worn clutch is the more likely culprit.
The reason to check the bearing, it is easier to change than the clutch.
The bell housing pan comes off with a few slotted screws. There is a small hole drilled in the bottom of the pan to let it drain. If there is much dripping from there, you probably have a dirty clutch.

Hi guys, thanks for all the info. I am off tomorrow so I will crawl under it and check things out. I will start with the drivetrain carrier then the KPs and then the pan under the clutch. I will let you know hownit turns out
Thanks Rick

Sounds like oil on the clutch disc. A quick fix is to put it in the top gear (4) rev the engine to 2500 rpm, and slowly release the clutch. This will burn off the oil, giving you smooth takeoffs again. Note, this isn't the best practice, as it may cause premature wear in the clutch disc, but if you have a rear leak, this is a much cheaper fix.

John

Hi, I found and checked the carrier bearing. It is as you said a short shaft then a long one. A steel bracket with a rubber inside and the DS running through it. It looks pretty good. I could move it about a 1/4 inch at the most but it is rubber. I was just really compressing the ruber. So I don't think it is that. I thought the 1" inch play was correct in the peddle, however after closer examination it moved about 1 inch but if I applied just a bit more pressure I could move it another 1". So I adjusted that and pressing the peddle feels much better. Didn't get to take the pan off yet. I will test drive it Sat morning. Thanks Rick

Hi, I took her for a test drive and adjuting the peddle seems to have helped a fair bit. I still need to check the oil leak but peddle and my driving seem to have improved things
Thanks Rick

My 1 Ton used to have clutch chatter starting off in second. My problem was that oil was leaking out of the transmission onto the shaft. I had it rebuilt and it is fine now. transmission oil laying in the bottom of the inspection pan can be really thick. Engine oil will not thicken.

Thanks Truckernix. I still haven't had a moment to check the oil part of it
Rick

I think by 58, those transmissions has a seal on the front to stop the lube from coming out onto the shaft. My 51 didn't have that. If it turns out that you have a preoblem there and you have a seal, you will be able to correct it easily.

Hi, I finally got under the truck and took off that pan. There was some oil around the edge of the pan. I wiped everything clean, stuck my hand and rag up inside . Didnt get to far in. There seemed to be a bit off dampness up there on the tranny side. But nothing that looked to serious to me. I am hoping it all boiled down to my clutch/foot skills and the peddle adjustment. I'll take her for another ride on Monday when I am off unless the snow flies. Then she'll be in for the winter.

Oil on the clutch is common. As stated above it can be burned off by trying to start off in the top gear. While stopped, place truck in 4th gear, rev engine to 2500 rpm and slip the clutch a couple times. Oil will be burned off, and smooth clutch action will be restored.

Thanks big, I'll try that Monday as well if problem persists.

Hey truckernix, I just realized you are from Bracebridge. I frequent the land of South River every summer. I've only been using this site for a few weeks but it doesn't look like there are to many from Ontario here

Rickyt,
I didn't notice your location either! I get around to the surrounding cruises in my area including Huntsville but I haven't made it to North Bay yet. Maybe you can stop by on your way up some time. We do have quite a few on here from Ontario. 1953 Panel is a regular contributor and he is not too far away from either of us.