68/70Vette
Well-known member
What are the largest size U Joints that can be used for a 70 Corvette driveshaft?
I purchased a TKO 600 and as part of the package I'll receive a new driveshaft. It's a Keisler TKO 600 kit. After installing the tranny and the differential they want you to measure for the driveshaft length...they tell how to measure, etc....so I did and called them up to order the driveshaft. My differential has a Tom's billet 1350 Yoke so I wanted a 1350 UJoint for the diff end of the driveshft. I asked for a 1350 U-Joint for the tranny slip yoke also. I was told, I could only install a 1310 U-Joint unless I wanted to cut an opening in the tranny tunnel. I didn't say anything, but this made me angry...why did I spend thousands of dollars buying high strength Tom's differential stuff (30/31 spline spindles, tuned differential case, hardened spiders, big half axles, and of course all 1350 U-Joints for the half axles) and $3500 for the 650 ft-lb rated TKO-600 transmission ...only to be told that I had to use a stock relatively weak 1310 U-Joint? One weak link just negates everything.
So....last Friday, I crawled under my 68, it has a TKO 600 and a 1310 U Joint. (It has basically a stock rear driveline with all 1310 U Joints). Sure enough it's a close fit. I estimate the 68's tranny slip yoke 1310 U Joint misses the tunnel by 1/4 to 3/8 of an inch.
So, my number 1 plan is to call back and order a 1350 U Joint for the tranny slip joint, anyhow. But I'm kinda leaning to ordering a 1330 U Joint. I know that the tranny slip yoke for the Richmond 5 speed uses a 1330 U Joint. I had no fit problem with this configuration in a 69 Vette. Also I think the L88 cars had 1330 U Joints. I bought a NOS driveshaft in the mid 70's for, best I can remember an L88. I still have the drive shaft and it's configured for 1330's. So what about ordering a 1330 U joint for the 70 tranny slip yoke? I have a 3.73:1 diff ratio, so the foot pound ratings from my driveshaft U Joints can be rated as 1/3.73 times the ratings of the 1350's??
Any of you running tranny slip yoke U Joints bigger than 1310's?
U Joint sizes:
1310: 3 1/4 inch yoke expanse, 1 1/16 inch cap diameter
1330: 3 5/8 inch yoke expanse, 1 1/16 inch cap diameter
1350: 3 5/8 inch yoke expanse, 1 3/16 inch cap diameter
Thanks
I purchased a TKO 600 and as part of the package I'll receive a new driveshaft. It's a Keisler TKO 600 kit. After installing the tranny and the differential they want you to measure for the driveshaft length...they tell how to measure, etc....so I did and called them up to order the driveshaft. My differential has a Tom's billet 1350 Yoke so I wanted a 1350 UJoint for the diff end of the driveshft. I asked for a 1350 U-Joint for the tranny slip yoke also. I was told, I could only install a 1310 U-Joint unless I wanted to cut an opening in the tranny tunnel. I didn't say anything, but this made me angry...why did I spend thousands of dollars buying high strength Tom's differential stuff (30/31 spline spindles, tuned differential case, hardened spiders, big half axles, and of course all 1350 U-Joints for the half axles) and $3500 for the 650 ft-lb rated TKO-600 transmission ...only to be told that I had to use a stock relatively weak 1310 U-Joint? One weak link just negates everything.
So....last Friday, I crawled under my 68, it has a TKO 600 and a 1310 U Joint. (It has basically a stock rear driveline with all 1310 U Joints). Sure enough it's a close fit. I estimate the 68's tranny slip yoke 1310 U Joint misses the tunnel by 1/4 to 3/8 of an inch.
So, my number 1 plan is to call back and order a 1350 U Joint for the tranny slip joint, anyhow. But I'm kinda leaning to ordering a 1330 U Joint. I know that the tranny slip yoke for the Richmond 5 speed uses a 1330 U Joint. I had no fit problem with this configuration in a 69 Vette. Also I think the L88 cars had 1330 U Joints. I bought a NOS driveshaft in the mid 70's for, best I can remember an L88. I still have the drive shaft and it's configured for 1330's. So what about ordering a 1330 U joint for the 70 tranny slip yoke? I have a 3.73:1 diff ratio, so the foot pound ratings from my driveshaft U Joints can be rated as 1/3.73 times the ratings of the 1350's??
Any of you running tranny slip yoke U Joints bigger than 1310's?
U Joint sizes:
1310: 3 1/4 inch yoke expanse, 1 1/16 inch cap diameter
1330: 3 5/8 inch yoke expanse, 1 1/16 inch cap diameter
1350: 3 5/8 inch yoke expanse, 1 3/16 inch cap diameter
Thanks
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