Shrockworks Skids and Cooling

[TerryD]

So I installed the full set of Shrockworks Skids on my Xterra and this weekend was the first real trip with them.

All weekend the Xterra was running noticeably warmer. The floor boards, shifter, and interior was really warm. Also, my electric cooling fan rarely comes on when trail riding, even in 90-100° weather and it was howling most of the weekend.

So I like the protection, but I've got to do something to fix this.

My first thought is longitudinal slots, 1/4-3/8" wide and roughly 4" long, staggered at 4" intervals on the engine and transmission skid. That would help with drainage and venting. Being longitudinal, they would be less likely to hang me for forward or reverse motion and drilling holes at each end should lower the risk or causing cracks. But it's 1/4" steel plate, so I can just weld up any damage easy enough.

I was also thinking about taking 6-8" off each side of the transmission skid to help the radiated heat from the exhaust system escape instead of continually heating up the skid and transmission.

I have bashed my factory engine and transfercase skids over the years but so far, haven't touched the transmission. I'm sure I'll belly it out eventually but I don't think narrowing that skid will cause any issues that having it full width would help me drive out of vs having to lift/winch the truck.

 

[Argan]

I am in Arizona and had the full Shrockworks skids front to back for over a year. Have not had any heating issues. I don't run a lot of trails, but our temperatures here are quite a bit higher than Virginia. Is it possible you have some other issue?

 

[Prime]

I was thinking the same. Although admittedly we have two different setups. The manual obviously doesn't circulate fluid like an automatic. And I got a new water pump when I had the chain guides done 40k ago. Plus I bought a CSF radiator when my OE one exploded. So my cooling system is probably in better shape. But I've been out in 100°+ Moab heat and have had no issues. Maybe my body lift allows more air to leave the front of the truck? Are you still running the OE fan clutch? I did have some cooling issues with the Autozone clutch even with the all aluminum radiator. Switched back to a new OE fan clutch and that went away.

Seems like the cooling system needs more attention than hacking up the skids.

 

[TerryD]

I was thinking the same. Although admittedly we have two different setups. The manual obviously doesn't circulate fluid like an automatic. And I got a new water pump when I had the chain guides done 40k ago. Plus I bought a CSF radiator when my OE one exploded. So my cooling system is probably in better shape. But I've been out in 100°+ Moab heat and have had no issues. Maybe my body lift allows more air to leave the front of the truck? Are you still running the OE fan clutch? I did have some cooling issues with the Autozone clutch even with the all aluminum radiator. Switched back to a new OE fan clutch and that went away.

Seems like the cooling system needs more attention than hacking up the skids.

If I had ever had any cooling issues before, I would agree. I'm still running the factory clutch fan and it works fine. It was locking up as well, which up until now was more than enough to keep up with the heat year round. Even wheeling around Colorado in 90-100°F heat my e-fan rarely ran so it running this often in 70-80°F temps was concerning.

It's not overheating, the skids are just restricting where hot air can exit under the vehicle and causing a lot more of the radiated heat from hot parts to be reflected back.

I may be one of the few people pedantic enough to notice this. I was driving bare foot and there were spots on my floor that were very uncomfortable for my feet because of the heat and the bottom of my water tumbler in the drink holders was quite warm, even being in the thick insert.

The body lift would allow a lot of heat to escape through the extra opening between the body and frame. I considered trimming my fender liners to allow the air to exit there at low speed but I'm not sure what effect it would have at highway speed when my wheel wells are pretty much pressurized because of the aftermarket bumper.

But that still doesn't help with all the heat around the transmission.

 

[IM1RU]

Full Shrock armor (MaxGear rear bumper).

I will agree that my cup holder area gets pretty warm, but I have never had any issues with the heat. I tow, I wheel, sometimes it's both at the same time. Biggest issue I have is climbing a grade while towing.... and that is just lock it in 3rd gear with the RPM's at about 4000 and 55 MPH.... as long as I do that the engine temps and transmission temps stay bellow 215- 220..... then return quickly to 200 or below once the grade is over.

Also I've been running this way so long I wouldn't know the difference.

 

[TerryD]

I did a fluid drain and fill on my transmission and it was burnt black and nasty looking. I was also starting to have shifting and TCC issues before the fluid change and with only 19k miles on it instead of the 30k I did previously.

After that I did a full flush and pulled the transmission skid off. I haven't been wheeling much this winter but I did run all of Uwharrie without the skid and my transmission behaved much better and didn't run my e-fan at all.

I've got several projects that are more pressing but this spring I'm going to look at cutting down the transmission skid or build my own that's narrower and allows more air flow around the transmission and exhaust.

 

[IM1RU]

That's just so weird.....

I tow with my truck, I do the poor mans' flush every couple years, trans fluid is always pink, and trans never gets above 212 on long steep grades pulling my trailer.... (I leave it in 3rd, doing about 3500-4000 RPM)

Are you re geared?

 

[TerryD]

That's just so weird.....

I tow with my truck, I do the poor mans' flush every couple years, trans fluid is always pink, and trans never gets above 212 on long steep grades pulling my trailer.... (I leave it in 3rd, doing about 3500-4000 RPM)

Are you re geared?

3.69 on 33s.

 

[IM1RU]

I don't understand why your experience is so different than mine. I'm 4.10's and 33's, but your gearing is really close to stock with that set up Stock equivalent from what I remember would be 3.73 and 33's.

 

[TerryD]

I don't know what the wheeling you do is like. East coast is hours of sub 5mph crawling in all temperatures. You could spend 10-15min on a single obstacle, scratching and clawing your way up.

 

[xyoverland]

Are you able to see transmission temps while driving? I’d be interested to see how yours compares to mine if we’re on the same trail. I also have the steel Shrock skids but of course smaller tires and 3.13 gearing.

 

[IM1RU]

I don't know what the wheeling you do is like.

Moab and Ouray

 

[TerryD]

Moab and Ouray

I've never wheeled there so I dont know what the pace and typical terrain is.

 

[Prime]

I've never wheeled there so I dont know what the pace and typical terrain is.

Moab: slow. No trees. Can be hot AF. Lots of steep climbs. Not a lot of airflow unless sand road.

 

[Brunnie]

Moab: slow. No trees. Can be hot AF. Lots of steep climbs. Not a lot of airflow unless sand road.

Ouray: slow, lots of stop and go. Trees and no trees. A little cooler. Lots of climbs over all kinds of stuff. Not a lot of air flow, so you use 4 lo a LOT.