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View Full Version : A arm cross shaft torque ?



dondb
02-12-2017, 07:51 AM
Just did the G mod and am installing Viking coilovers and Ridetechs Tru Turn. I have Hotchkis U/L a arms and the uppers come with offset cross shafts that put the upper arm rearward. I needed to flip the Cross shaft back to neutral (after the G mod) and the need to torgue the 22mm bolts back to spec. I called the Hotchkiss Tech line and they were not of any help? In this case the bolt size does not correspond with torque recommendation. Would anyone have any idea to what they originally torqued them too? Hopefully this has been addressed by someone here??

67rally
02-13-2017, 05:30 AM
Just did the G mod and am installing Viking coilovers and Ridetechs Tru Turn. I have Hotchkis U/L a arms and the uppers come with offset cross shafts that put the upper arm rearward. I needed to flip the Cross shaft back to neutral (after the G mod) and the need to torgue the 22mm bolts back to spec. I called the Hotchkiss Tech line and they were not of any help? In this case the bolt size does not correspond with torque recommendation. Would anyone have any idea to what they originally torqued them too? Hopefully this has been addressed by someone here??

50 lb-ft.

Although I'm sure most mechanics just torque it to "good and tight" since it may be hard to get a torque wrench in there depending on headers and where your accessories are mounted.

dondb
02-13-2017, 08:20 AM
Thanks for the reply Bret. I think you are referring to the cross arms bolts that hold the shims. I'm referring to the bolts that hold the cross shaft onto the a arm. They are 22mm's the bolts holding the shims are 3/8's. If i went by the bolt size and torqued it to that specification the cross shaft wouldn't swivel. I'm going to put it at 70lbs for now so i can continue with the build.

67rally
02-13-2017, 09:19 AM
Thanks for the reply Bret. I think you are referring to the cross arms bolts that hold the shims. I'm referring to the bolts that hold the cross shaft onto the a arm. They are 22mm's the bolts holding the shims are 3/8's. If i went by the bolt size and torqued it to that specification the cross shaft wouldn't swivel. I'm going to put it at 70lbs for now so i can continue with the build.

My mistake, I thought you were talking about the upper arm bolts that hold it to the subframe. Do you have to take the cross shaft out to flip it on the Hotchkis arms? On the SpeedTech arms, you can just rotate the shaft without taking those end bolts off.

So if 50 lb-ft is too tight to allow them to swivel, how did you come up with 70lbs instead?!?

dondb
02-13-2017, 09:52 AM
The Hotchkis cross shafts are offset toward the rear so when i did the G mod it doubled the distance toward the rear and hit my steering box. The cross shaft also can be turned to provide for shim adjustments if needed. So when i turned the shaft over it brings the a arm back to a neutral position to that of the orginal a arm allowing for the G mod to work. I don't think i said anywhere that 50Lbs was to tight.....what i meant was if i used the size of the bolt to get torque specs for a 22mm bolt it would be well over 100LBS:) I'm going to call Hotchkis and see if i can get the manufacturing engineer?

dondb
02-13-2017, 12:40 PM
Ok....the answer is they are not torque specific. They are done by hand in a vise. The cross shaft is put in a vise and the bolts are tightened an equal amount on both sides until the a arm moves very slightly under it's own weight. Makes sense since the bolts are like lock washers internally.

67rally
02-14-2017, 03:42 PM
Once you have it tightened by feel, maybe take a torque wrench to it to get a reading and post them here? I'm sure someone will stumble across this thread in the future with the same question.

67rally
02-14-2017, 03:47 PM
The Hotchkis cross shafts are offset toward the rear so when i did the G mod it doubled the distance toward the rear and hit my steering box. The cross shaft also can be turned to provide for shim adjustments if needed. So when i turned the shaft over it brings the a arm back to a neutral position to that of the orginal a arm allowing for the G mod to work.

I understood that, what I was asking is if you actually have to take the shaft out of the Hotchkis arms in order to flip the shaft for the offset. On my arms, you can just rotate the shaft 180 degrees without removing the end bolts.

dondb
02-14-2017, 05:40 PM
Brent...I tried to get the torque specs after the instructions were performed. But I got different specs. 25 lbs and 28lbs? So i took my calipers and got the bolts exactly onto the studs the same. I think because the bolts are self locking it gives different numbers. I hope this made sense? And yes I had to flip the cross shafts around to get it to neutral. Unless you have two sets of holes my arms would not work with the g mod unless they were fliped. Tru Turn showed up today:)

67rally
02-15-2017, 04:23 AM
My apologies to Don for not understanding what he was saying. He sent me pics and it cleared everything up for me. Sometimes a pic is worth a thousand words!

The Hotchkis cross shafts are offset in two ways. The shaft is offset so you can move the control arm closer or further away from the engine by simply rotating the shaft. Also, the bolt holes are not symmetrical, so you can take the shaft out and flip the shaft left to right to allow the control arm to move forward (toward the front of the car) or rearward. I don't believe my SpeedTech control arms have the offset mounting holes, which is why I couldn't understand taking the shaft out. I'll check again when I get home, unless someone knows for sure offhand.

Don's UCA's, top arm has cross shaft flipped:
https://static1.pt-content.com/images/pt/2017/02/4100096219F444328C00CD57F7AA5C26_zps1eb0-1.jpg[/URL]

andrewb70
02-15-2017, 06:54 AM
Where are these 22mm bolts? 22mm is almost 1"...are you referring to the socket size or the bolt shank size? Tongue specs are based on bolt shank size not wrench size.

Andrew

dondb
02-15-2017, 08:10 AM
Hi Andrew,
Yes the socket size. You can see the bolts holding the cross shaft on the a arm Brent provided above. The bolts on the shaft are put on by hand when it is put together at the manufacturer and torque is not used. Those 22 mm nuts are lock nuts and go on at about 25lbs torque all the way until they push up against the washer and bushing. Any more then that and the a arm does not articulate.

Rod
02-15-2017, 08:28 AM
good info, good thread, keep it up guys!