Lower a arm brackets and mounting

[phantom dually]

I went to bolt my lower arm to my 83 c10 tonight only to find out that the lower a arm mount that I have will not work. The holes to mount it in my crossmember are 2 5/8 from center hole to center hole. The stock 83 crossmember holes are 2 1/8 apart. I have a custom fabricated front crossmember in which I have already powder coated and have bolted to the frame. I have powder coated my a arms and all other components. Could this front crossmember posibly be from another year truck and bolted up to my 83? Does anyone know if the lower a arm shaft is a larger or smaller diamter in lets say the 67-72 trucks. I will atach pics below. Anyone that has any idea here please chime in and let me know!!! Notice in the pics that the holes do not line up.

[phantom dually]

heres another!

[phantom dually]

And another here where you see that the bracket I have is 2 1/8 apart from hole to center hole and the one below it is bigger 2 5/8.

[crazy longhorn]

Im not sure what caused the difference, unless maybe you have a 30 series crossmember(just a guess). my 69 measures 2 1/8 " center to center on the holes(20 series crossmember). This should apply to the 10 & 20 series for 67-72. My longhorn has 10 series lower arms, & spindles. The lower cross shafts measure right at 1 1/2 "diameter. From what i understand......you replaced the lower crossmember with a notched unit from a diff truck?

[CustomChevy]

one thing i did notice is that you do not have the support plate on the inner frame rail. there is a "angle plate" that fits right at the mounting holes to the frame on the bottom 3 and the side 2 bolts. this gave a big boost to front end structure.


for the lower arms, i would check bracket s from the 73-80 style and see if there was a change. there are numerous "subtle" changes in the 73-80 and the 81-87 trucks.

that powder coating looks sweeeet!!

[phantom dually]

Yes I bought the crossmember from a company in california. I have called the company and they are looking into it. I am very puzzled!!

[crazy longhorn]

customchevy, the C brackets go tween the crossmember & the shaft.........they are needed to locate the arm & also get proper stretch on the U bolts........crazyL

[CustomChevy]

crazy longhorn: you are absolutely right. guess i didn't word that very well. also seemed strange to see the brackets on topside. in any case, post has been altered, i am unsure if there was a change or not, but that could very well be one of those "subtle" changes.



good luck!

[crazy longhorn]

I havent been into the 73 up trucks too much , as far as swapping pcs, but it sure looks like they did something different. A lot of guys are opting to swap complete crossmember assys to avoid the missmatch in parts(not a bad idea ). I did the swap disc in pcs on my 69 (stock crossmember)& converted to 1/2 ton susp at the same time, & sorting out the steer linkage pcs was a bit of a headache. at any rate, good luck........crazyL

[bagged78]

Not to get off subject, but what was the company you got that from?

[phantom dually]

Turner enterprises in california. The owner bill turner is working on a solution and a answer as to why this member is diffrent. He has measued all other member that he has made up and they are all the 2 1/8 center to center as I need. This whole thing has us puzzled but he assures me that he will make it right!!!

[phantom dually]

By the way I have to use a fabbed motor mount instead of the traditonal angle plate that crazy chevy has spoke about. Since I haveraised the crossmember into the frame the motor would sit 2" higher if I used the factory angle plate and mount. Any questions on what the plate looks like I can post a pic!!

[CustomChevy]

phantom: that's pretty cool that the guy is gonna fix your prob. lots of places would probably say "sorry charlie". maybe he can hook you up with new brackets and u bolts to fit. didn't know you had the crossmember raised, that's pretty cool. let's see more pics when done. looks like a nice project!

good luck!

[phantom dually]

I will post some pics here as I start to bolt together. I dropped my rear housing off at the powder coater tonight and hope to start piecing the chassis together bolt by bolt here real soon. First I have to take care of the k member puzzle!!

[maritime_bowtie]

Hey phantom,
Could it be that when they made your cross member, they put the hole in the wrong spot? Weirder things have happened. I have a cross member in my basement off of an '85 and i measured it and the holes are 2 1/8. Maybe it was a shop error.

[phantom dually]

What they do is go to a junk yard and pull cross members from 1/2 ton trucks. They then take and notch it to fit up in the frame 2" and then they have to notch the front to clear all steering parts moving. I looked at it real hard a minute ago and it does not look like they messed with the mouning holes. I measured my old member from farthest hole to farthest hole and got about 20 1/8. The new member I have in the truck is the same. The inner two holes are farther apart and thats what throws me off. I am wondering if you can just bolt the a arm with a u bolt to the member without the brackets?? I doubt so but at this point Im still in the dark. Also one thing i notied is that there is not a hole for a rivet??

[maritime_bowtie]

I noticed that too, about the rivet. If you dont want to drill into your crossmember, you could always spot weld it in place, besides, it really shouldn't be able to go anywhere once its bolted on. I wouldn't mount your a-arms without those brackets though. Did the brackets come with the cross member? Maybe the brackets are off.

[phantom dually]

No the member was pretty bare. Another thing I just noticed is the upper two bolts that mount the upper a arm are a little bigger. Not much at all and the arms will still go on. I just mentioned this because its a diffrence. If it comes down to it I could have the two farthest holes welded up and then redrilled to match the brackets i need. If I am real careful not to scratch anything the bracket should cover up the welded area as to not be seen.

[maritime_bowtie]

Good luck, it sure looks nice.

[phantom dually]

Thanks i hope i dont run into anymore problems!! These things happen when you alter. Anyone else that has a 67-91 truck be it 1/2 3/4 ton please measure bolt to bolt on your front u bolt that holds your a arms in. Let me know what it is. My factory one was 2 1/8 apart center to center and the new member is 2 5/8. Let me know. Thanks

[maritime_bowtie]

Tell me this: the bolts used to bolt on your cross member and other front end parts, are they regular bolts, or high tensile bolts?
Does it really matter?

[phantom dually]

I used grade 5 bolts. I was told that grade 8 is the strongest as far as trying to be pulled apart but as far as a side impact they are weeker than a grade 5. I assume this is important in case of a vehicle wreck??

[phantom dually]

Found a 86 chevy van and also a 95 chevy van today that uses the same cross member and the bigger u bolt and bracket. I have got the vin # and hope to go thru gm to find a part. Every time I look it up in a part book it says that they are all the same but obviously theyare not. I am thinking the a arm that I have will work in conjunction with the a arm bar from the van and its brackets??? I will find out.

[bagged78]

Turner is mainly 67-72, maybe he sent you the wrong year! I thought they bolted up the same though.. Looks good, I hope you get it resolved..

[phantom dually]

He does mainly deal with 67-72 but as you said they are all the same. I have found the bracket I need but it is on the above mentioned vans. Im sure they would not like me taking there parts?? Anyhow I am calling tryingto find these parts new at gm. Theweird thing is they have the same part # for all the brackets from 67-94. It dont make any diffrence wheter it is 1 ton or 3/4 ton. I know that there is a diffrent bracket but GM dealers say that they only made one. If I have to I will be going to the junkyard to pulled lower a arms and u bolts!!!