Savvy vs Rokmen GTS

['05TJLWBRUBY]

Originally Posted by biffgnar

What does this mean? The northeast is not a particularly dry climate and I run multiple pieces of aluminum armor with no problems.

I'm curious too-the PNW isn't the most dry place in the world. I've run the gas skid in raw form since it came out several years back, and have been running the bumper raw for a couple years now as well. Having just pulled the fuel skid to modify it, I found nothing wrong or any issues anywhere. Bumper has been removed for engine work and no issues there either, though I'll likely paint it this time around.

Best of Luck,

Mike

[O_M_Jeep]

Sorry, bad math on my part, I was thinking about the cathode / anode / moisture issue, 6061 comes in about 0.15v, if it were closet to 0.96v the oxidation principals of aluminum would in direct contact with mild and alloy steel would make it a medium term solution, shorter half-life the more salt in the air or on the road

['05TJLWBRUBY]

Originally Posted by O_M_Jeep

Sorry, bad math on my part, I was thinking about the cathode / anode / moisture issue, 6061 comes in about 0.15v, if it were closet to 0.96v the oxidation principals of aluminum would in direct contact with mild and alloy steel would make it a medium term solution, shorter half-life the more salt in the air or on the road

So is salt the key here? I hear a lot of complaints from folks worried about galvanic corrosion from dis-similar metals. This probably isn't the place to ask but since you mentioned that, I'm really curious. Despite everyone so worried about it, the only ones I've seen with it were marine/salt based areas. In order to trigger the reaction, is the salt the key there or some other catalyst required? In the PNW running both fuel skid and bumper raw, I have had zero notable issues with this despite all the rain and snow, wet muddy trails, etc. Or is the make-up of the 6061 not enough to trigger? Just curious on the subject here, apologize in advance if this is the wrong place to ask.

BTW-I'm Not in the least saying everyone should run their aluminum skids raw, I was just doing some testing on the fuel skid originally to see how it held up to my environment long term. I coated it this time around with a shark hide clear coat stuff to try out.

Best of Luck,

Mike

[O_M_Jeep]

Saline is an impurity, as such it will increase the speed of the galvanic corrosion, but the only place it will be a concern within 3 to 5 years is amywhere the anodation layer is breached and at the bolt holes. The danger you understand is the abrasive nature of the aluminum dust created by the corrosion, ot does 2 contrary things, one is it eats in to the steel the aluminum is bolted to and 2nd, the powder welds itself to the steel and aluminum. Keep in mind with coating on the aluminum it takes time to happen, it speeds up slightly in high salt environs and when the aluminum is scratched, gouged or creased.

[imped4now]

Throw some paint on the mating surfaces at a minimum. No problem.

[Provelogear]

The steel flanges on the Savvy skid are zinc plated. I don't think anyone has even see very much galvanic corrosion on our skids in 3 years.

I would expect it on a boat not a Jeep.

[O_M_Jeep]

Like I said its long term, really not an issue in time frames under 5 years in coastal environments, you should search zinc + aluminum + galvanic corrosion, you might be surprised what you find in the metallurgy forums, especially ones about aluminum engine machining

[Provelogear]

Originally Posted by O_M_Jeep

Like I said its long term, really not an issue in time frames under 5 years in coastal environments, you should search zinc + aluminum + galvanic corrosion, you might be surprised what you find in the metallurgy forums, especially ones about aluminum engine machining

Please enlighten me I love to see what you have found.

I just know we don't have the heat or pressure of an engine and we don't see the corrosion like a boat. If you look at our Jeeps, you see plenty of steel to aluminum contact with very little if any galvanic corrosion. Even with the heat and pressure on a 4.0L engine, the many aluminum to steel contact produces very little corrosion. Look at the alloy wheels to flange or hub matings very little or no corrosion. This is were I base most of my observations not books or reports of possible reactions.

[Knuckelhead]

Originally Posted by O_M_Jeep

Like I said its long term, really not an issue in time frames under 5 years in coastal environments, you should search zinc + aluminum + galvanic corrosion, you might be surprised what you find in the metallurgy forums, especially ones about aluminum engine machining

How about all the aluminum to steel mating that's already in your Jeep?...

[Knuckelhead]

Originally Posted by Provelogear

Look at the alloy wheels to flange or hub matings very little or no corrosion. This is were I base most of my observations not books or reports of possible reactions.

And intake manifolds, transfer cases, bell housings, water pumps, alternators, winches, wheel lug nuts, aluminum radiators and I forget what else?...

[Provelogear]

I always thought galvanic corrosion was caused by the electrical current from a vessel's metal surfaces grounding to the water. That is why they have a replaceable anode that takes the hit.

Jeeps are more insulated (ie. tires) then boats so we don't see as much. I'm guessing here.

[Knuckelhead]

Originally Posted by Provelogear

Jeeps are more insulated (ie. tires) then boats so we don't see as much. I'm guessing here.

Do you have boat sides?...

[Provelogear]

Originally Posted by Knuckelhead

Do you have boat sides?...

[Dethplege]

Originally Posted by imped4now

Throw some paint on the mating surfaces at a minimum. No problem.

X2. This is common in aviation and handled as follows:

1 Spray Zinc Chromate to the aluminum mating surface
2 Spray metal primer or paint to the steel surface
3 Apply clear packing tape to either one of the 2 surfaces
4 Bolt it together sleep well knowing your fuel cell is happy and safer than ever

It's a wear item. If my Savvy fails due to chemistry I'll shave my head and sell my Jeep in favor of a minivan. To be fair, I'm not treating the mating surfaces. Pinky Promise.

['05TJLWBRUBY]

Originally Posted by Dethplege

To be fair, I'm not treating the mating surfaces. Pinky Promise.

I didn't treat a thing and haven't in the years since it was introduced and no issues. I see NO problem with this and no reason to worry.

I coated my gas skid with shark hide though when I re-installed it after the mods to it. The bumper will be painted when it's re-installed but only for a new look to match the rest of the rig. It's been raw for years with zero issues.

Just curious on the process behind it and the required catalyst-I hear enough worry about dis-similar metals with no real backup to prove it outside of marine use. Good info here.

Best of Luck,

Mike

[pcoplin]

Auto manufacturers have been making aluminum blocks with steel bolted all over them for decades. There won't be a problem.

[Dethplege]

Originally Posted by '05TJLWBRUBY

I didn't treat a thing and haven't in the years since it was introduced and no issues. I see NO problem with this and no reason to worry.

I coated my gas skid with shark hide though when I re-installed it after the mods to it. The bumper will be painted when it's re-installed but only for a new look to match the rest of the rig. It's been raw for years with zero issues.

Just curious on the process behind it and the required catalyst-I hear enough worry about dis-similar metals with no real backup to prove it outside of marine use. Good info here.

Best of Luck,

Mike

Whenever two different metals are in contact with one another in a non PH neutral environment, one will corrode more quickly than the other. Water carries salts - moreso near the coast - and also acids - moreso near larger cities. So over time it just happens. Accordingly, plummers are required to use specific couplers when connecting galvy to copper and aircraft mechanics treat surfaces as I mentioned above and so-on. Even two very similar metals will react this way. I've forever thought they mislabelled Locktite. More than keeping things from coming loose, it keeps bolts from chemically welding themselves in place.

Still inconsequential as it pertains to GTS's - I'd worry more about wearing stickers off of new tires.

[mrblaine]

Originally Posted by Provelogear

Please enlighten me I love to see what you have found.

Gerald, if you want some enlightenment, just know that this gentleman is Cryoming off of Jeep Forum. That will tell you more than you need to know.

[ytowntj]

Since you guys in your fancy desert dont see as much snow and salty shit as we do here (VA/WV mountainous area) Ill weigh in a bit on the real world corrosion issue. I put about 25k on my jeep a year, about 8-10k of that being on roads covered in a constant salt. This year not as bad, but usually 4 months straight of not being able to see the lines on most roads. This was my third winter with the skid and i have done nothing but wipe a layer of WD 40 on it a few times. I also drive on the beach about 5X a year dipping the whole jeep in some salty washouts along the way I recently had the skid off only to find about 2" of road salt/sandy muck inside the skid. I pressure washed it and there is no signs of serious corrosion. A few dark grain spots but no surface variations whatsoever. Another Ten years of this and there might be a slight concern of structural integrity (10%) but considering the stock skid was removed in about 10 pieces due to rust I see this as a non-issue. Im far more concerned with my frame rotting out (again) or the tub rails the body mounts attach to requiring repair for the third time (and yes I pressure wash the underside weekly)

The only thing that could use improvement that Ive seen is drainage. I realize this is difficult to do without weakening the skid or causing places to hang up on rocks...

[Bonofied Suiter]

I'd like to chime in on the fuel tank skid debate. I live in Las Vegas and so the corrosion issue doesn't really factor in for us here. I can say that I did a great deal of research three years ago when I was considering the purchase and had a hard time accepting that many of the skids I was considering added 50 or more pounds over the stock skid. There was no way I could feel good about adding that much extra weight to my Jeep. Then I looked at the Savvy aluminum fuel tank skid and how it only added a few extra pounds. I was also impressed with the engineering that allowed it to be raised significantly with a 1-1/4" body lift.

I bought our Savvy FTS prior to our first trip on the Rubicon trail. We only had 33" tires at the time and our skids (including our new Savvy fuel tank skid) took major hits on the hard granite. At the time it felt like we dragged our bottom over every boulder. Neither then or since on many trails throughout the western half of this country has our Savvy dented. It has a lot of scratches and a few gouges but no "Damage". It has taken on most of the famous trails in Moab including Pritchett Canyon and many of the trails in southern Utah, Nevada and Arizona. To say I am a fan of Savvy products would probably be an understatement. I now have the Savvy Under Armor and fully expect it to be just as tough as the tank skid. Why add hundreds of pounds of steel plate to your rig when for just a little bit more high tensile T6061 aluminum can do the job and add just a fraction of the weight of steel. That's what being "Savvy" is all about.

[Knuckelhead]

Yep, I've got one of the early Savvy GTS.

It's a very well thought out design and weighs 30 lbs less (with 3/4" more clearance) than the Kilby that I had...