Steering Box Upgrade

[JMT]

05 with the Mercedes steering box and 35’s. Would the PSC heavy duty steering box be sufficient to get those tires turning better, or do I need full hydro assist?

https://www.polyperformance.com/psc-03-06-jeep-tj-conversion-gear

 

[williambmac]

I have the same box in my Jeep. I do mild off-roading/fire roads, and it's been fine with 35's.

 

[TRE3TOP]

I’m not to this step yet, but I think it should help, just how much I’m not sure. It’s kinda a combination of all the parts though in the system. The bigger/better box, the higher flow volume pump and the ram assist. Are you trying to avoid hydro because of road driving or just avoid dropping 2k? Because I understand both.

 

[DougyintheBushies]

Interested. I’m getting this box too.

 

[JMT]

I’m not to this step yet, but I think it should help, just how much I’m not sure. It’s kinda a combination of all the parts though in the system. The bigger/better box, the higher flow volume pump and the ram assist. Are you trying to avoid hydro because of road driving or just avoid dropping 2k? Because I understand both.

What’s the problem with hydro assist and road driving?

I was trying to avoid the $2k price tag if this box is sufficient.

 

[williambmac]

What’s the problem with hydro assist and road driving?

I was trying to avoid the $2k price tag if this box is sufficient.

I've read that it makes road driving sketchy. Perhaps @mrblaine has better info.

 

[NashvilleTJ]

I've read that it makes road driving sketchy. Perhaps @mrblaine has better info.

You may be thinking of full hydro. There is nothing sketchy at all about hydro assist. In fact, it does almost nothing driving down the road.

 

[mrblaine]

I've read that it makes road driving sketchy. Perhaps @mrblaine has better info.

Hydro assist done correctly is 100% transparent. The rig steers exactly the same on the road as it does on the trail with zero discernible bad habits and the only difference is it turns on the trail easier than it did before.

 

[mrblaine]

In fact, it does almost nothing driving down the road.

When done correctly. I fix way too many of them that aren't set up correctly for that to be a given.

 

[mrblaine]

05 with the Mercedes steering box and 35’s. Would the PSC heavy duty steering box be sufficient to get those tires turning better, or do I need full hydro assist?

https://www.polyperformance.com/psc-03-06-jeep-tj-conversion-gear

Depends on how hard you need it to work offroad. Offroad, unless you add the higher pressure pump, it will be low on turning response due to the larger bore placing a higher demand on the system. You should also run a cooler in the grill. The box has enough power, but you need more pump to take advantage of the money you just spent.

 

[williambmac]

You may be thinking of full hydro. There is nothing sketchy at all about hydro assist. In fact, it does almost nothing driving down the road.

You are correct. I was thinking full hydro. A friend was running it on a full-size Blazer, and it was scary as hell on the street.

 

[mrblaine]

You are correct. I was thinking full hydro. A friend was running it on a full-size Blazer, and it was scary as hell on the street.

They can be set up to be far less scary and pretty nice to drive. I can't get past the fact that the steering wheel no longer has a center on most of them. That's enough for me to never do it.

 

[Irun]

05 with the Mercedes steering box and 35’s. Would the PSC heavy duty steering box be sufficient to get those tires turning better, or do I need full hydro assist?

https://www.polyperformance.com/psc-03-06-jeep-tj-conversion-gear

I ran the PSC box and pump only. It was a huge improvement over the stock box and pump. The upgraded PSC pump and box eliminated hard steering on the rocks and made my groaning stock pump a thing of the past. As was stated, a big cooler is a must, as is ensuring you set up the lines properly, and 100% eliminate air from the lines before running the pump.

That said, I seem to remember something being said about stress placed on one of the mounts (maybe track bar?) when running the PSC box and pump without the ram assist. Maybe @mrblaine can fill in the details here?

 

[mrblaine]

I ran the PSC box and pump only. It was a huge improvement over the stock box and pump. The upgraded PSC pump and box eliminated hard steering on the rocks and made my groaning stock pump a thing of the past. As was stated, a big cooler is a must, as is ensuring you set up the lines properly, and 100% eliminate air from the lines before running the pump.

That said, I seem to remember something being said about stress placed on one of the mounts (maybe track bar?) when running the PSC box and pump without the ram assist. Maybe @mrblaine can fill in the details here?

When we first started in 2000 with a big bore box from Lee Steering, we got that installed with a bumped up TC pump. In short order we cracked the frame around the box mount. We installed a steering brace over to the other frame rail. Then we cracked the frame around the trackbar mount. We installed a brace over to the other frame rail. Then we cracked the frame between the steering gear and trackbar mount.

Installed hydro assist to take some load off of the frame and removed the other two braces to never have another frame issue.

 

[TRE3TOP]

What’s the problem with hydro assist and road driving?

I was trying to avoid the $2k price tag if this box is sufficient.

I don’t think it’s a problem but the most common thing I see mentioned is it loses a little bit of sensitivity. Again I don’t have it so I dunno if that’s something that can be dialed out or if it’s a function of the pressurized ram creating less resistance.

For your needs, you can probably start with the box, or box and pump, and add the ram later if you still want more power. You don’t really save much if anything buying the kit vs piecing it all together.

 

[Lax22]

I’m running the original stock Mercedes box and pump tapped with a PSC trans/steering cooler combo and the BMB PSC ram and mounts.

It works great! I could probably benefit from an upgraded pump but so far the stock unit works well for me. I had tried to install the PSC stock replacement pump at the time of my install but it was faulty and I had to return it.

 

[mrblaine]

I’m running the original stock Mercedes box and pump tapped with a PSC trans/steering cooler combo and the BMB PSC ram and mounts.

It works great! I could probably benefit from an upgraded pump but so far the stock unit works well for me. I had tried to install the PSC stock replacement pump at the time of my install but it was faulty and I had to return it.

If you upgrade the pump, the steering will likely be too light feeling and not as much fun to drive.

 

[Lax22]

If you upgrade the pump, the steering will likely be too light feeling and not as much fun to drive.

I do notice that there is a bit of lag on the initial start up when the fluid is cold. It resolves pretty quickly.

 

[James C.]

I installed the PSC box / pump with Blaine's Cooler. Steering is definitely lighter on road as Blaine says. I haven't done anything I would consider "Hard Core" but I've done some trails and haven't wanted for more steering power.

PSCSR-VT - PSC REMOTE ANTI-SPLASH RESERVOIR W/ PRESSURE RELEASE VALVE​

PK1852 - PSC HIGH VOLUME STEERING PUMP KIT

SG400R - PSC EXTREME SERIES STEERING GEAR W/RAM ASSIST PORTS​

Additional items I needed were:
-8 Bulkhead fitting (PSC Reservoir comes setup for a -6 Return Line)
(97-02) lower steering shaft
(97-02) high pressure power steering hose
1/4" - 20 Rubber Well Nuts For 1/2" Hole

There is a wealth of knowledge on here and I suggest reading as much as you can and talking to Blaine before you buy anything.

 

[Gollywomper]

05 with the Mercedes steering box and 35’s. Would the PSC heavy duty steering box be sufficient to get those tires turning better, or do I need full hydro assist?

https://www.polyperformance.com/psc-03-06-jeep-tj-conversion-gear

Good news is the box comes tapped for assist. So if you decide you need it down the road your ready to go.