I'd guess the cooling is less - lower density across the radiator

however the times I've been to Colorado

normal driving was fine - but climbing mountain passes will heat up the engine

I70 headed out of Denver seemed the worst

but the only time mine ever got hot i.e. over 1/2 way on the gauge - was totally stock - i.e. thermostat and Fan clutch

_________________
2005 CRD
stuff
Skeptic quod gratis asseritur, gratis negatur

Only twice have I seen my temp gauge move to the right of center.
Both times were brief while in the mountains, climbing a steep hill, at slow speed.
And both times were after I removed my clutch fan.
This prompted me install a switch to give me manual control of the electric fan.

_________________
U.S. Army Retired

If by "cheap" you mean I carefully assess the suitability and value of every purchase before making it then I plead guilty as charged. Your solution is quality but imo it's also unnecessarily extravagant and let's face it anyone who cared about quality without concern for cost would not be driving a Jeep.

I don't expect you compromise on your asking price for me or anyone else and I certainly don't expect you to sell below cost. I was simply expressing the price points I would be willing to consider paying for any thermostat housing given the current alternatives. At the end of the day market forces will prevail and your sales will tell you what other owners think.

_________________
Share your ideas freely at https://www.facebook.com/groups/libertydiesels/

You have not data on the fuel savings.

Why don't you add in an alternator, battery, hood, windshield, etc. everything could be damaged.

My temp gauge has never moved right of center. It is always a C hair left of center. This was while I had the stant in for 50K miles or now since I did a timing belt change and replaced with a OEM t-stat. ( Thanks, Scott) The only time it ran cold was when the original OEM went bad. TDF, I believe your unit is probably the best but not for $500. Why are you giving Canadians a break on price?

My temp always is slightly left of center even though the OEM & stant are 20F apart in opening. I am able to use my Fia front all summer and the CRD will not overheat. I believe they both work efficiently. As you stated the engineers developed the t-stat, then why did they put in a lower temp t-stat. I believe the two greatest factors affecting mpg with the CRD are fuel & wind. I get 30-33 mph calculated with the CRD with the stant or OEM unit. The difference is due to wind or diesel quality. If you think I will get noticeable difference in mileage with your unit give me one & I will install it. I live in Flatland and will test the fuel efficiency. I get on the highway & drive 400 miles at a shot. I believe the major difference will be based on fuel & wind.

Correction:

The Stant works, but it is a risk... too many people have had cylinder head issues because of it. Ignore the bypass at your peril.

Just because a lot of people have installed in-line thermostat valves does not make them the correct upgrade. The R428 engine has had a lot of issues with head gasket failures, cracked and warped cylinder heads; the fact that this is a high compression engine with an iron block and aluminum head makes it vulnerable to such problems to begin with. Has it not occurred to CRD owners that a major contributor to these problems has been the use of an in-line thermostat?

You may be getting away with using an in-line thermostat because of the mild climate you live in, or your driving habits, or your CRD is merely a commuter vehicle and not a tow vehicle, or any combination of the aforementioned. Get a CRD into severe service mode, and all kinds of unexpected issues can pop up, including cooling system problems like overheating... just refer to mountainman's postings.

I'm the guy who posted in another thread that I noticed after installing HDS with the 203F thermostat that my shudder disappeared.

Some background: My 2005 Libby when in top gear cruising, light throttle, would buck or hesitate when a slight change in speed occurred, mostly at a slight de-acceleration, but never consistently or in a repeatable fashion. Since new I have done a number of upgrade such as the new fuel head and filters, replaced cracked air hose to turbo, eliminated the EGR assembly and piping, installed an Euro TC, replace the original thermostat with another OEM unit; I still would get a sporadic shudder at cruising speed. My next planned step was going to be to install the Carter fuel pump to the fuel tank.

Meanwhile I received the HDS and installed it. I am now on my fourth tank of fuel and so far the shudder has not occurred, and I have not changed anything about how I drive during commuting. The engine does appear to run much more smoothly to the point that even my bride is impressed. Before the HDS my mileage averaged 22-25 mpg, measured by miles driven and gallons pumped on fill up. After the HDS so far my mileage has been 23-25 mpg. One note to take is that now the weather has turned cold here my mileage usually drops to 18-22. If it stays up at 23-25 throughout the winter I will be pleased.

I can't explain it, but I suspect that my transmission is benefiting from the higher fluid temperature or the fuel injection is more efficient at the higher jacket water temperature, thus developing more engine torque, or a combination of factors. I'll continue to record mileage and see how this goes........

This Libby is at 190K miles and is on its 2nd tubocharger, pushing 245-70 series tires.

I agree that any inline option is risky business due to the bypass circuit.

I do not have and cannot afford the HDS, but it is the safest option if you do not want to go OEM.

I'm on my second OEM thermostat. I would love to ditch it and go with something that would allow for a hotter operating temperature, but for me running cooler is safer than leaving the bypass open.

_________________
2006 Jeep Liberty CRD Limited
Gen2 Fuel Head - Magnaflow Exhaust - Ram transmission swap - In-Tank Lift Pump
Moab Wheels - 245/75/R16 LR E Cooper Discoverer AT3 Tires - OME Lift 790/90009 948/60069 - Etecno Glow Plugs - V6 Airbox
RUNNING B100
Pic of my Jeep!

Only Jeff can comment on his pricing model but I suspect it's in US$ so he's kept his US$ price the same but not adjusted his CA$ price upward to account for our now crappy dollar. His labour costs are in CA$ so have not been hit by FX. His aluminum costs are based on US$ but aluminum cost has dropped significantly so his CA$ price for material probably hasn't changed much. His other parts costs are probably linked to US$ but relatively small.

The net result is that for every US sale he's likely covering more of his development costs (in CA$) on these than what he was when he first introduced the product and the exchange rate was close to par. Normally a weak CA$ is good for Canadian exporters because it allows them to become more competitive in the US. This equates to lower US prices and/or more profit.

I'm pretty sure he realises that, even though he's selling a premium product, if he jacks up his Canadian price to ~CA$700 he isn't going sell any.

_________________
Share your ideas freely at https://www.facebook.com/groups/libertydiesels/

If your shudder was caused by running cold then should you not still experience it during the warmup period?

Was your thermostat functioning correctly prior to the HDS upgrade? If not, what temperature was it actually running at? I don't recall if engine temperature factors into the decision to allow TC lockup but maybe if the engine is chronically cold beyond the point the transmission reaches operating temperature and the TC is allowed to lock up there may???? be some interaction.

I'll be interested to see what mileage you come up with versus a properly functioning OE thermostat.

_________________
Share your ideas freely at https://www.facebook.com/groups/libertydiesels/

I have never seen any data supporting that statement.

and it ignores the people who have had problems with totally stock systems

the very limited data we do have points to head problems being due to inconsistent 'torque to yield' head bolts

_________________
2005 CRD
stuff
Skeptic quod gratis asseritur, gratis negatur

You're right, I don't have the data, but if you jump over to ecomodder.com, you can find a descent approximation of what many things, like raising the temp 20 degrees with provide in fuel savings. I think the VW TDI is a good comparison, and I know there are many posts with approximate fuel savings for engine temp, warm air intake, and many others. I admit I would need to find a diesel with a mechanical fan for a good gauge on how much the real savings would be for removing it, but I've read of a few on cummins, and they were in the 1 MPG ballpark. 1 mpg is too little for anything less than one of the fancy fuel consumption monitors to really track accurately.

Dig around on ecomodder, or ask the question on how many MPG's 20 degrees will cost you in a diesel, and I bet you'll get some good answers. Lots of very knowledgeable people on there. I'm not really all that worried about it anyhow. $100 is too much to spend on a piece of trash that keeps my engine too cold. I'd rather spend $500 once, and be able to approach routine thermostat maintenance just like the old days, when they made things to last.

Giving Chrysler $100 for a stock thermostat is proving to them that they were right to stick it to you... It's a slap in the face for buying their product.

An inline? Well, I've already tested that thoroughly, and it's not good for heavy towing, or long mountain grades, or steep offroad trails that climb for more than a few minutes during the summer, even with a new Hayden heavy duty fan.

_________________
05 CRD: H.D.S2 stat,WW Ironrock trilink&LCA's, OX rear,ARB front, 4.10's, ARB bumper, Suncoast,OME 3.5, JBA UCA,rock rails, Moabs&265/75 Duratracs, GDE tunes ,FFD fan,ARP's, 2 micron fuel, new valves,sasquatch battery tray & grid heater, tensioner relocated
Mech fan, VH & AC delete

Quote from dirtmover: "If by "cheap" you mean I carefully assess the suitability and value of every purchase before making it then I plead guilty as charged. Your solution is quality but imo it's also unnecessarily extravagant and let's face it anyone who cared about quality without concern for cost would not be driving a Jeep."

#1) How can you assess the value of my thermostat when you do not even believe there is a problem with the O.E. thermostat? You wrote the following... "The fourth solution - continue to use the OE thermostats. I'm curious why you don't even acknowledge this as an option?" If you do not want to believe the opening temperatures of a brand new O.E. thermostat, then take the time to speak to any diesel engine technician about the use of a thermostat with that opening temperature on a diesel engine, and then finally come to the conclusion that all of us have already figured out, then there is nothing I can do to convince you.

#2) Is I have written ad nauseum on my thread, there was no viable choice for low production manufacturing other than CNC machining. A proper mold for the H.D.S. main housing and cap would set me back somewhere between $100,000.00 and $150,000.00. And no, sand casting is completely out of the question. Extravagance is a word that applies to something that does not have to be done, that it is completely unnecessary. When the ONLY option for a ground-up re-design is of anything is CNC machining, it is therefore quite inaccurate to call it "extravagant".

#3) Your are dead wrong with regard to people upgrading Jeeps... they are perhaps the #1 brand of vehicle that people upgrade, often with EXTREMELY expensive equipment and parts. The fact that the designs do not change very often makes them fairly easy to upgrade with very high quality expensive parts. Check out the following website...

http://bruiserconversions.com

You have mentioned that you were curious... now I have a question for you. If you think my product is a total extravagance, then how would you re-design the R425/R428 engine thermostat? I am really curious as to what manufacturing technique you would employ to get a reasonable quality re-designed thermostat assembly that can perform the same as mine and have the same features.

What do you mean by "inconsistent torque to yield head bolts"?

Essentially correct... I have kept my pricing consistent between U.S. and Canadian customers since the very beginning, and have only made a modest increase going from the first generation Model 001 to the second generation Model 001. The reason why the U.S. customers pay a little more is totally due to the poor performance of the Canuk Buck.

joelukex4; you wrote the following:

"As you stated the engineers developed the t-stat, then why did they put in a lower temp t-stat."

At first I simply thought is was a terrible mistake on their part... not the design of the unit but simply the low temperature opening. But I got into a discussion with another CRD owner a few months ago, and he thinks that it was deliberately done to fight "oxides of nitrogen" pollution.

If I recall correctly, the levels of oxides of nitrogen pollution increase with increases in engine temperature. Whatever the reason, although the basic design of the O.E. thermostat is sound, the opening temperature is WAY too low. I get a strange look from every diesel engine technician I broach the subject with.

The crazy thing is, while the low engine temperatures may lower NOX emissions, it makes the other pollution control systems unreliable. This tells me 2 things...

1) ...the vehicle manufacturers - except VW, of course - have their collective noses stuffed firmly up the butts of the EPA, CARB, and any other pollution control bureaucracy out there.

2) ...this is yet another example of how much contempt these same manufacturers have for the vehicle-buying public.

What he means is that the head bolts, as assembled from the factory, are not all tightened down the same.
Some are tight, some are looser, and some are so effing tight that the head of the bolt gets rounded off as you try to loosen it.

This is why ARP studs are recommended when changing the head gasket.
ARP studs dont stretch and you tighten the nut to a specific torque value that is consistent across the entire head.

_________________
U.S. Army Retired

My temp gauge has never moved right of center. It is always a C hair left of center. This was while I had the stant in for 50K miles or now since I did a timing belt change and replaced with a OEM t-stat. ( Thanks, Scott) The only time it ran cold was when the original OEM went bad. TDF, I believe your unit is probably the best but not for $500.

My temp always is slightly left of center even though the OEM & stant are 20F apart in opening. I am able to use my Fia front all summer and the CRD will not overheat. [/quote]

Jeff, why do I not see a difference on the temp gauge? Why does it not overheat? Has anyone checked temperatures while running an OEM t-stat? It may open at 175F but when running normally at speed is the engine closer to 195 F.

I must admit I don't know the workings of this cooling system but when the OEM thermostat is failed open and we are running an inline stat we are told the bypass is blocked. This is the main reason that the inline stat or a failed OEM stat is so bad for the CRD.

Are we to assume that no flow is taking place throughout the engine when the bypass is blocked. The water pump is still moving coolant through the block, heater core, EGR, oil cooler ultimately to the head. From what I understand with previous discussions there are numerous crossover hoses to the head. When I start my CRD until the time I have the gauge moving to the 1/2 point takes about 2 blocks of slow driving. Are we to assume that no antifreeze has moved through the head during this time and is creating hot spots?

Coolant is always moving. With a good OEM tstat when cold flow goes thru bypass not radiator as warms up tstat opens to block bypass and send coolant to radiator. Bad OEM tstat fails open or opening early sends coolant to radiator too early so system over cools and never warms up. When mine went bad at least during summer adding AC load would boost temp to normal but only in full AC mode

_________________
Sold to LOST member my 05 Ltd, GDE Stg II turbo + TCM tune, SunCoast TC w. Transgo kit, Steiger window regulators, Samcos, Fumoto valve, 2nd gen filter head with Lub. Spec. bleeder, Hayden clutch & 11 blade fan, inverted spare, P-1 battery, BF Goodrich Long Trail TAs, Etecno1 glow plugs, timing belt at 50K miles/8 yrs