I blew my rear u joint (driveshaft to Axle) and now im having a hard time finding a new one, i went to my local carquest and the u joints they had for the truck were all the wrong size.

Ive measured my okd u joints caps and i know two that are opposite of eachother are 1.125" or 1 1/8, the other two i dont know because i cut them off and i lost them. The u joint width i know is 3 5/8s across the one way and again i dont know the other way cuz inlost the caps,
All the ones at the oarts store had caps that were too big, there was one that was close but the guy behind the parts desk was a dumba $$ and didnt know how to use a caliper so he got a different number each time

Has anyone else ever had this problem trying to get new u joints? Ive searched google and i havnt been able to find any for the truck with the same dimensions of mine

 

year of truck, etc would help. someone may have done an axle swap at one point

 

Sorry completely gapped, its a 88 f350 single axle with 4x4 and full floaters, its just a reg cab and 8 foot box, also it was the driveshaft to diff u joint that i cant find

Doesnt look like the axles been swapped, it looks original but it is possible that its not

 

Body style (different wheel bases) transmission type, 4WD or 2WD can make a difference.

If it's the 88 F250 7.3 noted in your profile and it is Automatic 2WD it could be this first one in bold type below. $10.09 (USD) plus shipping from Rock Auto Parts. They are located in Wisconsin, USA - my favorite place to order parts and they are very highly rated, you can read about the company in the 'about' section. The url below:

CLEVITE / PERFECT CIRCLE 1204
Rear Joint; TO REAR AXLE 1 PIECE DRIVESHAFT,4 WHEEL/ALL WHEEL DRIVE and 3/4 TON and w/AUTO TRANS
Rear Joint; TO FRONT AXLE,4 WHEEL/ALL WHEEL DRIVE and 3/4 TON,CAP DIA 1.063" & 1.125"
Front Joint; TO REAR AXLE 2 PIECE DRIVESHAFT,4 WHEEL/ALL WHEEL DRIVE and 3/4 TON
Front Joint; TO FRONT AXLE,4 WHEEL/ALL WHEEL DRIVE and 3/4 TON,CAP DIA 1.063" & 1.125"

1.063" is probably rounded up from 1.0625 which is 1-1/16" I did not see any listings for all four caps or bearing sizes being 1.25 in.
There are LOTS of different u-joints (and sizes) listed from different manufacturers so read the specifications very carefully AND if you click on the 'INFO' button for each listing you'll get some additional information

RockAuto Parts Catalog

 

OH! Then I was looking at the f250 section at Rock auto. Try the 88 F350 4x4 at Rock auto. You'll find it.

 

When you get to F350 7.3L there will be a little search bar- just type in 'u-joint' without the quotes, hit 'Enter' and the list will come right up

 

1.063" is probably rounded up from 1.0625 which is 1-1/16"

 

Take the two caps you have, with whatever is left from the u-joint. See if it fits into the yoke on the driveshaft, meaning does the width look right? will the cap fit into the yoke?
Repeat this with the yoke on the differential.

If both sides are the same (and generally they should be....) you shouldn't have too much trouble finding a u-joint that will work. If the guy at carquest is an idiot, ask for someone else, or go someplace else. U-joints are specced with those two measurements, width of joint, and cap size.

Most u-joints are symmetrical. However, conversion joints are available, usually special order, that go from one size to the next. This could be needed if someone swapped a driveshaft or differential from another truck. I believe the diesel u-joints are bigger than the gasser ones were. When I did the 4x4 conversion on my truck I ended up with a gasser driveshaft that I needed shortened because the only diesel one I could find was bent.... I ended up needing the conversion joint to make it work.

 

Ok. I will definately try to see if the bearing caps fit in the drive shaft and yoke both ways.

I did search on google and on here for sites to buy a u joint and ive already been on rockauto but coukdnt find any with besring caps at 1 1/8" only 1 1/16 and the other sizes (1 3/8 and another size i cant remember) but i will look again when im home and can use a real computer and not my phone.

ThNks for all the help guys ill keep u updates

 

Also, not sure if it was a diesel or not but I have a '92 rear end in mine and its a '94. U-joints were different between the two.

 

Here you go
U Joints - Rear Shaft - 1988 Ford F-350 | O'Reilly Auto Parts

 

There they are: Bearing Cap Diameter (In): 1.063 X 1.125 Inch. Also listed at Rock Auto but O'Reilys should be able to get them over-night or even the same day if you order it early enough. Price will be a bit higher no doubt (one of the reasons I use Rock Auto Parts) but minus shipping cost at O'Reillys it might balance out.

I've not seen one listed anywhere with all 4 caps 1.125 inch so I doubt if they exist for this truck. Just match the length dimensions and you'll have the right one,. assuming the the one you pulled is the right one.

 

Ended up going back tonhe carquest and talked to a diffeent guy and what do ya know they had it there the whole time.
Thanks for the help guys

 

Isn't that the worst??? Drives me nuts... Stuff like that is why I bought my own calipers and search threads for part #'s and whatnot. If it saves me an hour driving to the parts store TWICE I'm happy.

 

Yes it does drive ya nuts lol, ive ordered parts from them before where theyve said itll be in in a week and i go to pick it up and thwy tell me that they dont carry the part and never even ordered it becUse they cant get one, ridiculous haha