Power steering with big tires on 4X4

I just put bigger tires on my 2000 Ram 2500 4X4 and they look awesome. I didn’t think about how the power steering would be affected, but at a stop or low speed, it is hard to steer. I had Lares rebuild the pump, since it had 100k miles on it, then the steering gear. The front end was checked for obstructions such as worn parts, but everything looks fine. With all the lifted trucks that have bigger tires, is there any aftermarket pumps to steer better, or is it something you just have to live with? I have had many Dodge and Ford trucks, but never with oversized tires.

Hydro assist will help. You'll need to get a different steering box with extra ports and a hydraulic cylinder. You can drill and tap the steering box yourself, if you're willing to take yours apart. Lots of info on 4x4 forums to sift through about box tapping, hydraulic cylinder stroke length, pump mods, hose routing, power steering reservoirs, etc. You can also probably get a kit from PSC, but it'll cost some money. A good power steering cooler is also a good idea, if you do any off-roading. I've had a steering pump so hot, it seized up, and water would steam off of it. It's amazing how much stress large tires put on everything.

Wide tires have more rubber on the ground at one time then more narrow tires have, making them harder to turn. Wheels with a smaller backspacing move the tires away from the centerline of the truck, requiring more effort to make them turn. Taller tires with more profile have more sidewall flex the shorter sidewall tires. They don't necessarily turn harder, but it takes longer for the turn to take effect. Your "bigger tires" could have all 3 things going for them, which all effect the truck turning experience in a negative way. Depending on how carried away you got, it may well be something you have to live with.

Modern trucks are built closer to the weight and height load requirements then trucks of the past were built to. Older trucks tended to be overbuilt, so there was an extra margin of safety, but the modern trucks often have a higher capacity then even the over build of the older trucks. One only needs to look at the max capacities to understand that todays trucks are expected to carry more weight.

All that said, even back in the late 70s and early 80s, bigger tires on trucks caused a lot of problems. Wheel bearings, and cracks around the steering box mounting on the frames were pretty common issues associated with mounting larger tires on a truck then it was built to use.

Oversized tires exceed what your truck was designed to have and use. How far oversized did you go?

stop cruzing the mall parking lot, it will steer fine in the mud with less traction and more wheel speed. you know "scratchinfotraction" LOL!

try turning 17/44/15 Ground Hawgs on 14" wide 4.5 backspace - Bart super trucker rims on a D44 front axle LOL! 6" skyjacker lift 440/435/205 D60D70-4.56 lockers. 3500rpm 3rd gear low range walks the dog all day.

I just spoke to Cal at Lares. These guys know their stuff. He thinks the check valve located behind the hi-pressure line is stuck, because of improper bleeding procedure. He said to take line and fitting off, push valve a couple times to free, and bleed by starting from center, and turning wheel one eighth turn each direction and then further each way until air is bled out. I will be trying that this week. Thanks for the replies, will let you know how it works.

lift tires off the ground with that procedure, that way it is not a high load on the pump/box while bleeding it.

please update your results when done.

My daily driver 95 2500 had 39.5s on it for years and it did fine. That being said I would say I was pushing the limits of the stock setup. I still have the truck and it will be getting hydro assist when it goes back on the street.