Can I jailbreak my iPhone 4 on 4.0 firmware or do I have to upgrade to 4.0.1?

[LyricalMenace]

I am using iPhone 4 with stock firmware 4.0

Can I use the jailbreakme.com method with this firmware or do I have to upgrade to 4.0.1?

I have read several problems with 4.0.1 being a bit slower, or buggy, or even draining more battery. My phone has been working fine now and don't see any reason to upgrade firmware, unless I have to do jailbreak.

So do I gotta upgrade or will I be safe at 4.0? Gotta find out before apple throws the new firmware out and screws me.

Also I plan on using the restore feature on itunes before doing the jailbreak to get a clean install. Will this restore my iPhone to 4.0 (original firmware) or will that automatically make me go to 4.0.1 firmware?

 

[LoLife]

You can jailbreak on 4.0, I did it.

When you sync to itunes it will try and get you to upgrade to 4.0.1 just make sure that you don't agree to it. It will ask you to upgrade and you have to accept it if you want to. Pretty sure anyway haven't upgraded through itunes in a long time

 

[F123D]

I'm jailbroken on 4.0 (don't like the new signal bars) and it's working flawlessly.

 

[LyricalMenace]

Did you do a fresh restore before you JB?

I don't mind doing this, but just wanna make sure the restore is gonna restore my 4.0 firmware and not try to force me into 4.0.1

 

[chargit]

if you do a fresh restore through iTunes you will upgrade. you need to do a restore from a backup and then you wont. but honestly just backup your phone and jailbreak and you will be fine. no need to restore first.

 

[calvy]

I originally jailbreak mine on 4.0, but then wanted to do the commcenter patch to enable native tethering, and had to be on 4.0.1 for that. I'm not noticing any major problems on 4.0.1 personally, and the signal bars don't seem drastically different to me. I still get full bars pretty much most places.

 

[LyricalMenace]

Yah still on the fence about 4.0.1

Anyone have any input on it?

 

[dhlizard]

Yah still on the fence about 4.0.1

Anyone have any input on it?

I like it but of course what the signal bars look like is not important to me. Just that I can make a phone call every time I want to.