Thursday, May 1, 2008

Steering Box Lubrication

Steering Box Lubricant

As part of the routine maintenance on the 1955-57 Thunderbird, the level of lubricant in the steering gear box should be checked at least once a year. This applies to manual as well as power assisted steering units. This came as a surprise to me. I assumed that if there were no signs of leakage from the gear box that everything must be fine. I did not take into account the fact that over the years. as the seals on the gear box became brittle. the lubricant leaked out long before I bought the car. The result was a car with no lubricant in the gear box, thus no leaks! The only signs of trouble would be a car that was hard to turn. In power steering equipped cars, this would be only slightly noticable.

To check to see if your gear box has the proper level of lubricant is actually quite simple. The gear box is located at the base of your steering column and is mounted on the inside of the frame. By looking straight down inside your engine compartment. the top of the gear box housing should be clearly visible at the base of the steering column. The top of the housing will have two very noticable hex bolt heads. The two bolts are of different size. The smaller of the two bolts will be located "off center" and closer to the frame. This bolt will have a bleeder cap on top of it. The bleeder cap will look like a round rubber tip with a small hole in the center. The center bolt is the larger of the two. This bolt does not need to be disturbed to check or add lubricant.

To check your fluid level, you need to remove the small hex head bolt with the bleeder cap. Check to make sure that the bleeder cap is loose as it sits on top of the bolt. If it is not, once removed you should clean it thoroughly. With a flashlight, look inside the hole where the bolt was removed. You should be able to see the inside of the gear box. The gear inside the box should be completely immersed in lubricant. If not, you need to add 90 weight gear lube to your steering box. If there is no lubricant present, your gear box seals are probably in need of replacement. You can check by adding gear lube and look for leaks. As an alternative to gear box rebuilding, you can add STP oil treatment. The STP oil treatment is thicker than 90 weight gear lube, but yet fluid enough to ensure proper gear lubrication. By being thicker, the STP should resist leaking out of the gear box. If the seals on your gear box are not completely disintegrated, this "quick fix" should be all that you need to do. Your wheels should turn easier and your wallet will be happier. Once again, I thank Ken Smizinski for providing this month's "tech tip."

1 comment:

Anonymous said...

My 57 Ford Thunderbird had occasional steering "moans" when turning slightly. Checked the steering box and it was dry! Filled with SAE 90 oil and moaning disappeared. Great, but then I found a huge leak of the installed oil on the garage floor. Looked at information to remove and repair the steering box..way beyond my capabilities! My question is, would adding STP oil treatment work to stop the leaks? Or could I fill the steering box with standard lubricating grease instead?