TR2/3/3A TR3 Steering: Penrite v. Snythetic

[Mkutz]

I'm in the final stages of finishing my TR3 resto and am about to fill the steering box. I bought a bottle of Penrite, but have yet to put it in as I am considering a synthetic 75w90 gear oil instead. I checked out the Valvoline bottle yesterday, and it says that it is a fine replacement for GL5 gear oils, and other extreme pressure applications.

Obviously, I'd rather make the right decision before topping the box off. The box was rebuilt by TRF a few years ago, so I don't forsee any leaks. Anyone have any opinion on this? Would a GL5 synthetic oil have any bad effect on the internals? Is it safe to assume that only a pint is necessary to fill the box, and is the fluid filled to the where the fill plug is?

Thanks for everyone's help!

 

[TR3driver]

I've been using Valvoline full synthetic 75W90 in my TR3A steering box for quite a few years, and it works fine for me. Don't recall just how much it took initially, but it was less than the quart that the oil comes in. I use the same oil in my Triumph differentials, so it didn't really matter to me.

There are two "fill" plugs, both a hex head plug on the box itself, and a rubber plug farther up the steering column. You can fill to the opening for the rubber plug, but it's really only important that the oil cover the top of the worm, below the lower plug. I add a few ounces at every oil change to bring the level back up to the rubber plug.

Hmm, that reminds me, I don't think I filled TS13571L. Better do that.

 

[glemon]

I'd use the Penrite, even rebuilt boxes have a tendency to leak or at least weep, penrite minimizes this, I have used Penrite in a box that had been leaking gear oil pretty well, the Penrite fixed it. I think both would work fine as far as lubrication is concerned.

 

[Geo Hahn]

I use the Penrite in an older box that is somewhere between 'as new' and 'needs rebuilding'. As a slow leak was the only complaint I had about the box the Penrite seemed right for me and I have had no problems.

With a rebuilt box you are probably good either way... the oil is certainly cheaper but the quantity is small so not expensive either way.

 

[prb51]

The 75/90 would be slipperier and flow better..if the box is rebuilt I'd go with that....if you end up with leaks then try the Penrite, that's what it was designed for.