steering effort

[paloaltohh]

Dinan Performance Engineering used to offer a steering modification for the 750 that would allow the driver to dial in the steering effort at higher speeds rather that have the factory computer settings determine the effort for you. They no longer offer this modification because of liability concerns. I have had my car for fifteen years and my only complaint is the heavy steering, heavier even than my motorhome.
Is anyone aware of a modification that would increase the servo boost at highway speeds? It is obviously possible because Dinan used to advertise it as the TURBOTRONICS 8 for an installed cost of $994 in a 1999 brochure that I have.

[libertylover]

<i>I have had my car for fifteen years and my only complaint is the <b>heavy steering</b>, heavier even than my motorhome.</i>

Heavy steering? You must have a problem in the steering because my steering is as light as a feather at low speeds. It's fantastic! Certainly one of the best features of the car. It is speed dependent though so it still feels solid at higher speeds.

Your system probably "thinks" it's at high speed all the time and thus at low speeds it's heavy. It probably happened so gradually that you hardly noticed, like needing glasses.

The Bentley's manual says, "An electronic/hydraulic valve on the steering gearbox controls power steering assist via the Servotronic electronic control module".

Bentley's lists 3 things for "Heavy Steering":
1-Worn upper strut bearings;
2-Incorrect tire pressure (nahhh)
3-Power steering system faulty

For #1 it says to replace the bearings of course. For #3 it says to check the power steering fluid level and test system pressure.

Also, a 750 has a LAD, self-leveling rear suspension system that shares a pump and fluid with the power steering system. Don't want to insult your intelligence but, if you haven't already done so, check the fluid level and remember that it takes a special fluid. Depending on the year it takes either Pentosin CHF 7.1 or Pentosin CHF 11S. It says on the top of the canister which one it is. The dealer is the only place I've found this stuff and it's about $20/liter.

Hope this helps.

[paloaltohh]

Libertylover, thanks for your comments. The steering is fine at low speeds, but the highway feel is much heavier than I would like; however, I think that is my problem since I am used to much lighter sports cars and I would like my 750 to drive like one. You mentioned Bentley, which I assume is a repair manual. Would it by any chance have a detailed schematic of the power steering system? If so, maybe that would give me a clue as to how to prevent the system from reducing the hydraulic assist as speed increases. It might be something as simple as disconnecting a speed sensor wire.

[libertylover]

What year is your 750? Send me your email address and I'll see if I can send you the right pages. Better yet, send me the last 7 characters of your VIN. Email me at:
[email protected]

[libertylover]

paloaltohh, you've got mail!