I'm doing the stronglifts 5x5 and the weight for me now on my squats is getting quite heavy (127.5kg - 280lbs?), and I'm getting a lot of pain in my elbows, and my arms are pretty much dead after the 5x5 squats. I'm guessing this is because I'm probably using my arms to much to stablise/hold the weight as I come back up on the squat.

What I dont know how to do is fix this though, is this something I can work out with a simple change, or is it time to deload as the weight has got to much? Any pointers would be good, I dont want to blow out my elbows!

I am stretching (doing shoulder dislocations etc.) so this is different from the last elbow pain thread I posted! :)

What I dont know how to do is fix this though, is this something I can work out with a simple change, or is it time to deload as the weight has got to much?

The answer is probably "both, sort of". By that I mean that you probably could have adjusted your form so the bar's weight is resting primarily on your torso rather than your arms, but it sounds like you've got some degree of injury to your arms that you should attend to before you try to fix your squat technique.

I'm not sure how low-bar squats work, but with high-bar squats, your shoulders/back should be holding the bar up, and your arms should only have to stop it from rolling/sliding around. I can't say much more without seeing your technique, though - maybe someone else has more insight.

My understanding of low bar squat is that your torso should still hold the weight, and this is probably my problem in that I may well be holding the bar to low...

Ripptoe has a primer for this on his site. He says to use a suicide grip, thumbs on the same side as the fingers, not too wide of a grip and to make sure your elbows are pointed towards the ground. That advice helped my elbow pain.

Already use the suicide grip, though will have to check where my elbows go. I have a feeling they may point back a bit.

honesty:

Stretch your external shoulder rotators and increase your thoracic mobility. A problem with either one will affect your ability to rotate your forearms backwards. And when that happens, your elbows take the brunt (it's like you are doing an americana on them.)

Shoulder dislocations are good, but specifically look for stretches for the external shoulder rotators. Hit that **** hard and often, and you should see a tremendous improvement in a manner of weeks.

One tip with shoulder dislocations. Don't use a dowel. Use a rope instead. And when you grab the rope, pull it away as if you were trying to rip it apart. It is counterintuitive, but in doing so, it loosens up your shoulders and shoulder blades, facilitating rotating your arms back and forth.

Also, take a dowel and perform behind the neck presses... by the 20's, 40's or hundreds. The idea is not to press anything heavy, but to press something behind your neck for reps and increase your shoulder mobility.

Check your posture in the mirror, if you hunch forward that means your chest muscles are tight (and perhaps suffering from protracted shoulders and/or wing scapular syndromes, which will affect your ability not only of doing squats but also bringing the bar behind your neck.

Great thanks! Any specific stretches I should be looking at for thoracic mobility?

Sorry, looked myself and found this on stronglifts for thoracic mobility:
http://stronglifts.com/how-to-improve-your-thoracic-mobility/