BHRIG

What is the correct fluid in the steering box

Can gear lube be use?

Thanks in advance

0Willcox Corvette

I only use Chassis grease.. you don't want to use a fluid, it will leak out on you!

Willcox

7T1vette

You want gear grease. And I prefer synthetic gear grease for the steering box because of the better oxidation (aging) and heat resistance characteristics.

Jim Shea

The engineers at Saginaw Steering Gear always told me to use a good grade of lithium based chassis grease. GM part number 12377985.

A certain rebuilder uses Costal Uniplex premium, high temperature, lithium complex grease. He does not use synthetic grease.

Jim

BHRIG

Thanks for the swift response!
Lithium chassis grease it will be.

0Willcox Corvette

Didn't have the p.n handy Jim.. but this is the same stuff we use.

7T1vette

OK, I'll 'bite'. What's the concern about using synthetic gear grease in the steering box? It's a unit that has low-speed bearing operation, extremely low-speed gear tooth mesh (sector gear), and some bushings. It also sees significant temperature differential (cold ambient to exhaust temp) and lengthy operational use without service. That sounds like the perfect reasons to use synthetic grease [which I do]. Where's the risk in using it over the 'old tried-and-true' lithium grease {which, at the time of these car's manufacture was the best thing available...and it isn't, anymore}?

Rally68

I have the same question...i have a couple tubes of royal purple ultra performance grease, and i was going to use them for my steering box rebuild...

jb78L-82

Gary, GTR1999, just rebuilt/blue printed my OEM box and I spoke with him in person about the issue of synthetic versus non synthetic grease. The short simple answer is that he told me that he stopped using Mobil 1 grease since the box will weep the red grease out of the gasket since the temperature changes cause expansion and contraction. Customers didn't like seeing the red grease marks on the side of the case. As I recall, it has nothing to do with the qualities of a synthetic grease versus a non synthetic grease. BTW-the original factory grease looked great after 33 years and the gears were perfect so probably not imperatively necessary to use synthetic grease on a rebuild. Hope that helps!

7T1vette

The solution to that 'problem' is likely to be: Don't stuff the box completely full of grease. It needs some expansion room, so leave a little bit of air space in it. Also, use a synthetic grease that doesn't melt at "modest" engine compartment temps. Mobil 1 synthetic grease melts at 200 degrees or so??? Not a good synthetic grease, if that is true.

Still no good reasons not to use good quality synthetic grease, IMO.

P.S. I've used synthetic "GreenGrease" for a couple of years now, with absolutely no problem. It's good for up to 500 degrees, so it won't melt easily. It's available in many 'corner' auto parts stores. Check it out... [www.greengrease.com]

bashcraft

There also aren't any good reasons to change over to it.

7T1vette

Like... it doesn't dry out...and...it doesn't melt???

I didn't make any claim that using white lithium grease would not be good. But it, like all organic grease compounds, does have the above listed "problems".

My question was "Why not use synthetic grease?" I never indicated that one shouldn't use regular organic grease if they choose to do so.

bashcraft

I haven't had those problems with oganic grease in my steering box.

7T1vette

Good for you!!! Other folks do.

0Willcox Corvette

For me it is not a matter of synthetic lube vs. standard GM chassis grease. I use what has worked for me time and time again. It may fall under the "it ain't broke" law, or the old "I'm hard headed and won't change" rule, I've not checked.

The main point about grease vs. oil is a different story and I feel it is important for people know the difference. GM has not used oil in the gear boxes since the 50's and most people do not realize this. What people see in an old box when torn down gives them the impression the box was full of oil when in fact; the residue present is the residual effect of the original grease breaking down.

Jim Shea

Quite frankly, I would follow the suggestions of Gary Ramadei who has rebuilt hundreds of Corvette manual gears. Unfortunately, he no longer posts on this forum so we don't benefit from his direct feedback on things like this. I am sure that Gary knows not to overfill manual gear boxes when he rebuilds them. I know that he used to recommend synthetic. If he reports that his findings are that some gearboxes leak red synthetic grease and it looks bad, then I am inclined to follow his advise.

7T1vette, I am glad from your sample size of 1 or 2 that you haven't seen any problems with synthetic grease. Either way, whatever type grease is used, we don't have a show stopper.

Jim Shea

jb78L-82

Here are some pictures of the steering box before and after in the rebuild/blue print process from one of the best at making your OEM box better than new after 33 years and 65,000 miles (hint-it's NOT me, Gary Ramadei, referenced above by Jim Shea):

vetteguy75

Not to steal this thread, but how do you 1)make sure you have enough grease in the steering box and 2) if not, how do you refill it while it's still in place on the car?

...Roger...

I use a standard grease gun, remove the upper and lower bolts in the cover,gun in upper hole and look for grease in lower.

7T1vette

Exactly! But, leave some air space for expansion of the grease when it heats up. As long as the mechanism is covered by grease, there is plenty in there. (reference above photos)