I know there's a bunch of threads out there about this but none of them seem to fully agree or have the bolt sizes. My leaf springs have been shot for awhile but I'm finally replacing them with a friend on Wednesday (in 2 days) before I drive 300 miles home from school. He works at a shop with a lift so I'm bringing it in after my last final to try to get this done in the 3ish hours before the shop closes.

Everything is so rusted out and corroded under there that I want to replace the shackles and hardware too (spring bolts, u bolts, the plate above the spring where the ubolts bolt to, etc). But I can't find out what sizes everything is. I'm trying to figure that out today so I can order the right size parts and have them overnighted here so I can get this done and get home without any problems. Or so I can just go to a hardware store and buy the correct size bolts just to hold it together till I get home and can buy the correct grade stuff.

I believe I have the Dana 35 axle, but I bought 2.5" ubolt kit from autozone and they seem a little too narrow to fit around the axle but the 3" was way too big. I don't know if I should find a size in between that fits easily or if I should heat the 2.5" and then force them on. The replacement springs came with new bushings so they are fine. If I can get the shackles in on time they too have a new bushing but no hardware. If I can't get those in on time, I'm gonna have to keep the rusty shackles but replace everything else.

I tried getting under the jeep last night with a ruler to measure everything but it was too cold, dark, snowy, rusty, and awkward to get any accurate measurements of the stuff already on there.

If anybody knows the dimensions of the right hardware to get please let me know (ideally by noon on Wednesday so I can buy it on my way to the shop). This is a rush job cause I want to get out of here and get home for break but I want to do it safe enough so nothing blows out on me on the drive.

Thanks in advance to any help. I really appreciate it. -John

 

What size did you end up using for the leaf spring bolts?

 

If I'm correct, it should be an M14x120mm coarse. (2mm thread)

I ordered them in class 10.9/yellow zinc for mine. Here's to hoping I got the right size (LOL)

 

Diameter of a Dana 35 is 2.75", that's the size you need for U-bolts.

The bolts that hold the leaf springs in are ISO Class 12.9 (roughly equivalent to SAE Grade 8, but NOT Grade 8) M14x2.0 120mm flange head. Same size for front eye, rear eye, and shackle. If you can't find flange head make sure to get appropriate Class 12.9 hardened washers or close-fitting Grade 8 hardened washers. The OE nuts are not of the locking type by the way, so if you get those (nylon not being a really good idea considering the stress these are under) the torque specs will be off.