U-joints

[Jeffrey G.]

I'm installing a new clutch,u-joints'etc.in my 64 365HP 4 speed. How do I get the trans. back in with the bell housing installed? They had to come out together. The rear u-joint is 3 1/4x3 5/8x1 1/16. I can't find one in any of the catalogs. Has anyone run across this?

[Larry M.]

Re: U-joints

The correct driveshaft for your car has a removable front yoke. So you separate the front yoke from the driveshaft and insert it into the trans rear section as far as it will go. Maybe put a bit of light oil or Vaseline on this yoke to avoid any damage to the trans rear seal during this step. You then line up the rear driveshaft yoke to the rear axle and insert the u-joint and finger tight the strap retaining nuts. Then you simply pull the front yoke back to meet the driveshaft and install the front u-joint and straps.

Then tighten all u-joint strap retaining nuts (8) and you are done.

If you have a different type driveshaft than this, you can change it to the original type, or figure out another way to do the job.

As far as the dissimilar sized u-joint, they are available and I believe were used for the late 70's or early 80's Corvettes etc. Google u-joints for Corvettes and see what are available sizes. It should be in the list. Others may have a part number for you if you wait a bit.

Larry

EDIT: Here is a link to this dissimilar/specialized u-joint. https://www.dennysdriveshaft.com/p37...t_3_732_x.html It is a greaseable u-joint with blue seals. You may want one that is non-greaseable with black seals as a better match to original. Just do a bit or searching and you will find it. It is a 1310 to 1330 series combination u-joint

EDIT2: Here is a link to the front removable yoke. From Paragon #1702. https://www.paragoncorvette.com/p-35...-yoke-kit.aspx

EDIT3: Here is a google search for the 1310 to 1330 u-joint. Enjoy. https://www.google.com/search?client...UTF-8&oe=UTF-8

[Joe L.]

Re: U-joints

I'm installing a new clutch,u-joints'etc.in my 64 365HP 4 speed. How do I get the trans. back in with the bell housing installed? They had to come out together. The rear u-joint is 3 1/4x3 5/8x1 1/16. I can't find one in any of the catalogs. Has anyone run across this?

Jeffrey------


Your application originally used 1310 series driveshaft u-joints, front and rear. This is one of the most common u-joints ever made. It has a width at both trunnions of 3.22" and a bearing cap OD of 1.06".

What you are describing is a CONVERSION u-joint which is a 1310/1330. Such a u-joint was never originally installed on any 1953-96 Corvette. When found on a 1963-70 Corvette, it's usually the result of a conversion to a 1971-74 Muncie transmission or conversion to a 1971-79 rear end with a 1330 series input yoke and either conversion using an original driveshaft with 1310 series yokes.

Such u-joints are currently available but not from GM. Simply ask a driveline parts supplier for a 1310/1330 conversion u-joint. A Dana-Spicer 5-134X is one example of an available 1310/1330 conversion u-joint.

By the way, when new u-joints are installed on a driveshaft, the complete assembly should be rebalanced at a competent driveline shop. When conversion u-joints are installed or replaced on a driveshaft, the driveshaft assembly MUST be re-balanced.

[Jeffrey G.]

Re: U-joints

Thanks for the information. I ordered a Moog 253. This is a great Corvette but full of surprises! To get the transmission out I had to drop it and the bell housing at the same time. Do you think I can get the trans back in if I install the bell housing first?

[Edward D.]

Re: U-joints

Jeff,
Yes you can install the bell housing first. You have to have the motor tilted down in back. You should have removed the shielding over the distribution cap and the tach cable as this can hit the firewall ledge. You should have a board and jack under the oil pan to support the motor. With the motor tipping down in the rear you can lift the trans and push the tailshaft (no yoke installed on tailshaft yet) as far as possible over the cross member with the shift sidecover pointed down. Then raise the nose and the shaft should just clear the bell housing, rotate back 90 deg to normal after this. Rest the nose of the trans shaft inside of the opening of the bell housing. Then jack the motor up to a more level position (you must do this or you will not be able to slide the trans forward) . A helpful hint here, get a couple of 3-1/2" bolts same size as trans mounting bolts, cut the heads off, you will use these as guide pins when sliding trans forward thru clutch and into pilot bushing. Install these guide pins in two upper holes of the bell housing trans mount. Then, lift trans and push forward onto guide pins so that shaft goes thru throwout bearing and into pilot bushing. Did I mention that the motor has to be jacked back up to level before you do this? very important. If the trans doesn't slide all the way forward don't panic, just slide the rear yoke in, put it in any gear, and rotate the yoke a bit to turn the input shaft a bit. I've left a lot out, I'm assuming your pilot bushing in the end of the crankshaft will accept your trans input shaft end. If you removed and replace the bushing (a good idea) be aware that the new bushings compress when installed (reducing the inside diameter) and may need to be reamed to size to allow the trans input shaft to go in. Always use an impregnated sintered brass oil-lite pilot bushing (should not attract a magnet), many if not most of the replacement bushings available these days are crap. At any rate after you slide trans home then put in lower bolts, remove your upper guide pins and install bolts. Then do your rear trans mount bracket. Finally, remove jack from under oil pan and install rear slip yoke and driveshaft. Caution on installing new u-joints in driveshaft, you need to do these with a press and be careful as it is all too easy to bend the driveshaft yoke and ruin a perfectly good driveshaft. Questions? Just ask, I do this a lot in my shop.

[Joe L.]

Re: U-joints

Thanks for the information. I ordered a Moog 253. This is a great Corvette but full of surprises! To get the transmission out I had to drop it and the bell housing at the same time. Do you think I can get the trans back in if I install the bell housing first?

Jeffrey-----


As I mentioned previously, for your car to have a conversion u-joint installed, the car must also have a non-original, 1971-74 Muncie transmission or a 1971-79 pinion flange. Out of curiosity, which is it? Is the conversion u-joint installed at the rear or front of the driveshaft?

[Jeffrey G.]

Re: U-joints

Rear of driveshaft. Why would a 71 to 79 pinion flange get installed?

[Joe L.]

Re: U-joints

Rear of driveshaft. Why would a 71 to 79 pinion flange get installed?

Jeffrey------


Most probably because the entire third member was swapped out for a 1971-79 unit. Usually, if someone swaps out a third member like this, they don't want to change the pinion flange to the correct one. It's much easier to just install a conversion u-joint.

Please check out the stamping on the bottom of the cast iron carrier case. It will be found on the very bottom, adjacent to where the cover attaches. Report what you find and we can tell you what you have.