Lifting a Truck or SUV - Prone to Mechanical Problems?


#1

I have a Tahoe with a 6" lift, and it seems that it has been nothing but problems. Near Diff went out and I have had to replace the front sway arms, ball joints and rods twice in two years. I want a truck, should I avoid lifting it?


#2

I’m assuming that when you added the 6" lift you put on 31" or 32" tires??? If so then yea that’s the MAJOR cause of your problems. I don’t like lifts on trucks for MANY reasons…One being safety…Not to mention the fact in MOST states it’s illegal.


#3

In short. Yes. It likely was the cause of your problem and yes you should avoid doing so with your next truck.


#4

31" tires are stock on a Tahoe (metric equivalent of a 31 anyway).

With a 6" lift he can run 33-35in tires.

Lifting a truck is legal in ALL states, there are rules though: http://www.offroaders.com/info/tech-corner/lift-laws.htm


#5

I have had numerous lifted trucks and have had great success.

It sounds like the lift you bought was not well engineered; there is lots of junk out there for lift kits. There are also good quality lifts out there that will significantly increase the strength of the suspension over the stock setup.

The issue with your rear end exploding is probably from the larger tires. What size are you running? Your Tahoe has a 1/2ton rear end with an 8.5in ring gear. Max reliable tire size for this axle is 33in.
You can buy a 9.5 in 6-lug 3/4 ton axle that is a direct-bolt in replacement for your 1/2-ton rear. With the 9.5in rear you can easily handle up to 37in tires, though with your lift and 1/2ton IFS I would not go above 35in. I run a 9.5in rear in my Blazer and it’s a huge improvement strength wise with only a minimal loss in ground clearance (I also shaved 0.25in off the bottom of the axle for more clearance)

A great recourse for more info is here: https://coloradok5.com/


#6

I take it you didn’t actually READ the article. Please show me how you can lift a truck 7" WITHOUT raising the bumper???


#7

I’m assuming by “I have a Tahoe with 6’’ lift” as opposed to “I lifted my Tahoe 6"” that you got the vehicle with this already done. The other posters are correct about increased stress on the diff’s and potential legal consequences, but I would also suggest that a vehicle that has been lifted has probably been beat up a little. It is done sometimes as a fashion statement, but I’d assume someone who lifted it also took it on all sorts of off-road adventures which may not be the best for the long-term reliability of the truck.


#8

You must be talking about NH. As long as the bottom of the bumper is not higher than 20" it’s not a problem. There are bumper drop brackets that can be purchased or easily fabbed to lower the bumper. Some people also install reomoveable bumpers below the origional, or just removable dropped bumpers, that can easily be pulled for better approach/departure angles off-raod.


#9

I also forget to mention body lifts:
4" suspsension lift + 3in body lift = 7in and bumpers will be legal on most trucks with this setup (bumper on goes up 4in). Another advantage to this method is better driveline angles.

This obviously doesn’t work on unibodys though.


#10

You must be talking about NH. As long as the bottom of the bumper is not higher than 20" it’s not a problem.

I raise the bottom of my STOCK 4RUNNER 6" and i’m OVER the 20" limit. And that’s WITHOUT putting on 33 or 35 inche tires. Take a full size F150…add 6" lift and then put on 33" the front bumper is over 2’ off the ground.


#11

From the article link you posted…raising a truck 6" and putting on 33" tires the following states it will NOT be allowed.

Alabama
Arkansas
California
Colorado
Connecticut
Delaware
Florida
Georgia
Idaho
Illinois
Indiana
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Nevada
New Hampshire
New Jersey
Now York (Depending on year)
North Carolina
Ohio
Pennsylvania
South Carolina
Tennessee
Utah
Vermont
Virginia
West Virginia
Wisconsin

Of the states I didn’t mention some state the vehicle may or may NOT be legal. The headlights CANNOT exceed 54" above the ground. Take a truck like a F150…add a 6" suspension lift and 33" tires…the headlights will EASILY exceed 54".

It comes down to how much lift and how big the truck is to start with. After doing some quick calculating…a modest 2-3" lift is acceptable in MOST states…Anything above 6" with larger tires and it will fail in a VAST MAJORITY of the states. Only a handfull have NO lift laws.


#12

You are making gross generalizations to try and prove your point. A 6in lift is legal in most of the states you listed for most trucks.

I’ll demonstrate your flawed math on the headlight point. I don’t have an F150 to measure, but hear are how the #'s will play out for an 86 K5 Blazer and a 2005 Dodge 1/2 ton with a 6in lift and 35in tires (this is a very common combo for full-size trucks):

Chevy: 31 inch stock tires
stock headlight height = 42in
42 + 6 + (35-31)/2= 50in

Dodge: 31 inch stock tires (metric equivalent)
36 + 6 + (35-31)/2 = 44in

This lift law debate is doing nothing to help the original poster. So I suggest we drop it and start a different thread if the point still needs debating.


#13

I suggest you actully READ the article this time…Only about 10 states use Headlight to determine if the truck is too high. Most of the states that have laws use Bumper height. Many even have a specific law saying you can’t raise or lower the vehicle more then x amount.


#14

yup. I know. I’ve been doing this for over 10 years.

You brought up the headlight thing, so I tried to demonstrate the flaws in your logic. I can’t realistically illustrate every possible lift scenario for every state with every vehicle. You made some pretty broad generalizations that just aren’t true.

The laws vary greatly from state-to-state however, lifting and oversize tires are legal in all states. The maximum height and how that is determined is what varies.


#15

can’t realistically illustrate every possible lift scenario for every state with every vehicle. You made some pretty broad generalizations that just aren’t true.

From you’re previous statement…

A 6in lift is legal in most of the states you listed for most trucks.

You’re the one who made the BROAD statement…that a 6" lift is legal in MOST states…ALL the states I listed a 6" lift would NOT be legal. ALL those states base their calculation on BUMPER height or have laws saying you can only raise or lower the height by at most 3". So in MOST states a 6" lift is NOT legal.


#16

I’ll not comment on the legalities of lifts as that wasn’t what the OP asked about. My comments are based on 20+ years of Jeep experience, but I find that the principles carry over to other vehicles.

First, there are generally two components to driveline failures with lifted vehicles: driveline vibration and axle failure. Both can be traced to improperly installed lifts.

The driveline vibration generally results from incorrect pinion angle which can be addressed from several approaches. Most typically, a motor mount lift and/or transmission case drop will bring the system close enough to eliminate the problem. With extreme lifts, the pinion angle must be adjusted by wedging the rear axle or otherwise turning it so that the pinion points at the correct angle towards the driveshaft. The driveshaft may need modification with a slip yoke eliminator and CV joint to complete the job.

Axle failures can usually be attributed to using a weak axle with oversize tires, plus liberal applications of the gas pedal, especially when offroad. The oversize tires are not only heavier, but their greater diameter also effectively raises the gear ratio, putting additional strain on the differential, axle shafts, and housing. As previous posters indicated, the best fix for this is to replace the original axle with a heavier duty one, which may come with heavier duty brakes as well. A quality lift kit will come with all the required parts, including upper and lower control arms, sway bars, links, etc. It’s not cheap.

I have found that the stability problem, for reasonable lifts, is probably more apparent than real. You can watch these vehicles offroad and see some pretty extreme lean angles without overturning. I wouldn’t recommend anything extreme for the street, however.

All said, a lift is not a simple thing and should be carried out by someone with experience. Properly done, it should not affect the longevity of the vehicle or drivetrain or result in driveablity problems.


#17

Didn’t I already address the bumper issue?

3in suspension lift + 3in body lift = 6in, bumper is only raised 3in. This is just one solution of many to satisfy the bumper requirements.


#18

3in suspension lift + 3in body lift = 6in, bumper is only raised 3in. This is just one solution of many to satisfy the bumper requirements.

I’ll agree with that 100%. I don’t mind trucks being raised…just the ones that are now a safety problem for other vehicles. A mother and child in the town I lived in where killed because the truck behind them was raised up almost 2’. Instead of his bumper hitting the bumper on her Camry…his truck when right OVER her car…crushing her and her 2yo.