It seems like the question comes up all the time and I know that Greg's Lift Overview does not include leveling, so I figured I would add a new thread dedicated to this.
The biggest thing that determines how much lift you can get in the front to level your truck depends on the year of your truck and if you are 2wd or 4wd:
'04-'07 2wd: 2.5"
'04-'07 4wd: 2"
'08+ 2wd: 2"
'08+ 4wd: 1.5"
If you keep your leveling kit at or below these numbers, you SHOULDN'T have coil bucket contact, although sometimes very minimal contact can occur. If you go over these numbers, you will more than likely need aftermarket upper control arms or will at least need to grind down your coil buckets.
Options for leveling:
1) Spacers - these are the cheapest route and can be found at prgproducts.com. You can also find these all over ebay, but the big thing you want to make sure you do is get a solid billet spacer. These are much more sturdy than the other options and will last longer over time. These spacers will maintain the stock ride while helping to reduce the rake of the truck.
2) Bilstein 5100's - think of these as a 1/2" spacer, although they have the ability to lift your titan more than that. These have three different lift settings, .5", 1.5", or 2-2.5". The ride will get firmer as you go higher with these and there are very few people on the site using the highest setting. However, NO MATTER WHAT SETTING YOU USE, IT STILL ONLY COUNTS AS A 1/2" SPACER. Example: Bilstein 5100's on any setting count as a 1/2" spacer, so a pre '08 4x4 could use a 1.5" spacer plus the Bilstein 5100's on ANY setting, and it will work (total of 2" spacer). These are a substantial upgrade to the ride of the stock shocks. For more information on these, check out this thread: 5100's Install and Tips.
3) For pre '08 titans and '08+ 2wd titans, you can upgrade your coils to the '08+ 4wd coils. There are many write ups on this mod, so I will not go into details on this. Here is a good one from recently: '08 + Coils and 5100's
4) Rough Country 3" Lift: this lift comes with aftermarket upper control arms as well as the spacers. For '08+ 4wd titans, it has been recommended to not go with the full size spacer that this kit comes with because you will more than likely still have coil bucket contact. You can talk to Rough Country when you order this kit and ask them for a smaller spacer, which should be a 2" spacer.
5) Lifting the rear: this can be achieved using a block and will maintain the stock ride. However, it is recommended to get the front of the vehicle done first to see how big of a rear block you need. You can also use Deaver Packs, which can be found here: PRG Products - Rear Suspension.
6) Lifting higher than the recommended heights: you can do this, but as I mentioned, you will at least need to grind down your coil bucket lips and you might still need aftermarket upper control arms as well. Options for aftermarket upper control arms include Rough Country (1/2" more lift allowed), PRG, and Total Chaos (1"+ more lift allowed).
One other thing to note is that after any of these lifts, an alignment is always recommended. If you are an '05 or later, you will more than likely need new camber bolts to get your alignment set correct. These can be found on PRG's website as well as at any auto shop or even on ebay.
I know I have probably missed a few things, so if anyone has any other notes or tips, I would be happy to add them to this thread!
The biggest thing that determines how much lift you can get in the front to level your truck depends on the year of your truck and if you are 2wd or 4wd:
'04-'07 2wd: 2.5"
'04-'07 4wd: 2"
'08+ 2wd: 2"
'08+ 4wd: 1.5"
If you keep your leveling kit at or below these numbers, you SHOULDN'T have coil bucket contact, although sometimes very minimal contact can occur. If you go over these numbers, you will more than likely need aftermarket upper control arms or will at least need to grind down your coil buckets.
Options for leveling:
1) Spacers - these are the cheapest route and can be found at prgproducts.com. You can also find these all over ebay, but the big thing you want to make sure you do is get a solid billet spacer. These are much more sturdy than the other options and will last longer over time. These spacers will maintain the stock ride while helping to reduce the rake of the truck.
2) Bilstein 5100's - think of these as a 1/2" spacer, although they have the ability to lift your titan more than that. These have three different lift settings, .5", 1.5", or 2-2.5". The ride will get firmer as you go higher with these and there are very few people on the site using the highest setting. However, NO MATTER WHAT SETTING YOU USE, IT STILL ONLY COUNTS AS A 1/2" SPACER. Example: Bilstein 5100's on any setting count as a 1/2" spacer, so a pre '08 4x4 could use a 1.5" spacer plus the Bilstein 5100's on ANY setting, and it will work (total of 2" spacer). These are a substantial upgrade to the ride of the stock shocks. For more information on these, check out this thread: 5100's Install and Tips.
3) For pre '08 titans and '08+ 2wd titans, you can upgrade your coils to the '08+ 4wd coils. There are many write ups on this mod, so I will not go into details on this. Here is a good one from recently: '08 + Coils and 5100's
4) Rough Country 3" Lift: this lift comes with aftermarket upper control arms as well as the spacers. For '08+ 4wd titans, it has been recommended to not go with the full size spacer that this kit comes with because you will more than likely still have coil bucket contact. You can talk to Rough Country when you order this kit and ask them for a smaller spacer, which should be a 2" spacer.
5) Lifting the rear: this can be achieved using a block and will maintain the stock ride. However, it is recommended to get the front of the vehicle done first to see how big of a rear block you need. You can also use Deaver Packs, which can be found here: PRG Products - Rear Suspension.
6) Lifting higher than the recommended heights: you can do this, but as I mentioned, you will at least need to grind down your coil bucket lips and you might still need aftermarket upper control arms as well. Options for aftermarket upper control arms include Rough Country (1/2" more lift allowed), PRG, and Total Chaos (1"+ more lift allowed).
One other thing to note is that after any of these lifts, an alignment is always recommended. If you are an '05 or later, you will more than likely need new camber bolts to get your alignment set correct. These can be found on PRG's website as well as at any auto shop or even on ebay.
I know I have probably missed a few things, so if anyone has any other notes or tips, I would be happy to add them to this thread!