Cold Jeep Questions

KrazyJeeper

New member
I have two questions, first, this morning was very cold, below freezing and I usually don't wait long after cranking the motor up to back out of the drive, well this morning, it seemed like the Jeep hesitated going into gear for a second or two. Is this something I should worry about?

And second, I know Jeeps don't have the best heaters in the world, but mine will not warm up at all while just idling in the drive, you actually have to get it out and get the RPMs up and then it still takes a long time for any heat, probably 6 or 7 miles at least. My other TJ and XJ did not do this. Help. Thanks
 

Krazy Jeeper...I had a Honda that had that same issue with warming up, changed the thermostat and what a huge difference! Car warmed up before I got to work.

I'm not sure what temperature thermostat a jeep runs but I am sure that will make a difference.

Susan
 
definately replace the thermostat. I replaced mine and made a huge difference. when i bought mine i had a choice between a 160 and a 195. these are the rated temperature at wich the thermostat opened. for more heat go with a higher temp rating. i put in a 195 and it will get hot within about a mile. before it would barely warm up at all and if i got on the interstate all the heat would escape immediately. also a soft top will not hold the heat as well as a hard top.
 
Thanks folks for the troubleshooting. I have priced them and they are really cheap, but now I wonder how hard is it to change out on your own. I have a buddy who is a mech, but would kind of like to teach myself. Thanks again, KJ
 

It's an easy fix, pick up a repair manual if you have any doubts after looking at it.
 
"Follow the upper radiator hose until it connects to the thermostat housing.(where the hose meets the engine block). Remove the bolts securing the housing to the motor. Remove old thermostat and scrape the melted gasket from both surfaces and clean thouroughly. Install another gasket and thermostat ensuring it is in the right direction."
 
You stated two problems here...


I have two questions, first, this morning was very cold, below freezing and I usually don't wait long after cranking the motor up to back out of the drive, well this morning, it seemed like the Jeep hesitated going into gear for a second or two. Is this something I should worry about?

I take it that you have an automatic transmission. Just like the motor your transmission needs time to warm up. During the initial start up most of your transmission fluid is in the transmission pan, as the motor runs it starts pumping the fluid through out the transmission including the transmission cooler where it takes some of the motors heat to warm it up. Giving it a minute or two to throughly fill all the valves in the transmission, and get up to some what operating temperature is a wise idea.
Just like any oil the transmission fluid also lubricates the gears of your transmission, and when its cold, the fluid is less viscoses (fluidly).
Just like any fluid the transmission fluid can freeze (but a very low temperature) but during the coldest parts of the year it can loose some viscosity so allowing it a minute or two to warm up will prolong the life of your transmission.

Take a look at your fluid level (after the vehicle is warmed up to operational temp and the transmission in neutral. The fluid should be bright red and up to level on the dip stick. Even a 1/4 of a quart down can affect the transmissions ability to shift on an incline. If its slightly brownish you should schedule an appointment to have your transmission flushed and the filter changed. I do mine every 15,000 miles. Since your in Texas I also recommend that your run a external transmission cooler in series for the summer months.
Just dropping the transmissions temperature 25 degrees can extend the fluids life by 10,000 miles. Heat is the number 1 killer of all automatic transmissions.
I was told that it should be running around 150 degrees Fahrenheit, mine runs at 157 on most days during the summer months, and 145 during the winter so far( changed mine this fall).
I run a large external cooler made for a large Doge pick up down stream from my radiators cooler then back into the return line. I also added a deep well transmission pan from Mopar (53$) that added about 2.5 quarts of fluid, that came with everything you need to replace the pan. Gaskets, new filter and the extender block to lower the filter and pick-up tubes for the deeper pan.

If you decide to go this route take a week while your painting the pan to use PB-Blaster to help un-freeze the six bellie pan bolts and the rear transmission mount bolts (the ones bolted through the bellie pan).


P.S. Mopar makes a deep well transmission pan for all the wranglers and Grand Cherokees, unfortunately they don't have one listed for the XJ's. I will add the Mopar part numbers later.
 

Utah J. well you kind of blew my mind since I am not tech savvy but I did read your post over and over and did what you instructed. The transmission fluid level was way below the min mark. I checked it last night but not by your instructions. Learn something new everyday. The dipstick states use dextron II or something else. Which do you recommend? And thanks, but I think I still have a T-stat issue, the upper hose is slightly warm while the smaller hose was fairly hot. Yeah, I know, my terminology sucks, but thanks again! KJ
 
Utah J. well you kind of blew my mind since I am not tech savvy but I did read your post over and over and did what you instructed. The transmission fluid level was way below the min mark. I checked it last night but not by your instructions. Learn something new everyday. The dipstick states use dextron II or something else. Which do you recommend? And thanks, but I think I still have a T-stat issue, the upper hose is slightly warm while the smaller hose was fairly hot. Yeah, I know, my terminology sucks, but thanks again! KJ

if you want to pay more for Dexron III then be my guest:-) local service shop I use when I don't have time to do things puts dexron II in transmission and Transfer box. just as good for the jeep and a whole lot cheaper.
they also agree with utah J that heat is a killer and all bits of the jeep benefit from regular fluid changes including the engine oil.
 
Utah J. well you kind of blew my mind since I am not tech savvy but I did read your post over and over and did what you instructed. The transmission fluid level was way below the min mark. I checked it last night but not by your instructions. Learn something new everyday. The dipstick states use dextron II or something else. Which do you recommend? And thanks, but I think I still have a T-stat issue, the upper hose is slightly warm while the smaller hose was fairly hot. Yeah, I know, my terminology sucks, but thanks again! KJ

Hopefully you did check the fluid while the jeep was running and in neutral, any other method will give you a false reading. As to what fluid to add, Dextron II is fine, there are several manufactures and its ok to mix MFG's when topping off.
It was 22 degrees last night and when we went to dinner it took about 5 miles or so to warm my 01 TJ up to 210 degrees normal operating temp.

I am not sure what year your wrangler is but it shouldn't matter, your local parts store can help you with the recommended type of antifreeze. My 01 uses the red type, I would have to venture out to the garage to find out the type.
If your jeep takes longer than 5-10 minutes to warm up, its most likely your thermostat, there designed to fail in the open position, thus not giving you the proper pressure to heat the anti-freeze at start up, then open to cool the motor after it reaches operating tempature.
If you think this might be the problem, I recommend that you buy a thermostat, and radiator cap at the same time. The seals in the cap can degrade over time to slowly let pressure out, a white spotting around the cap and or radiator neck is a sure sign that you need to replace it.

Not knowing how long its been since you changed/flushed your radiator. I do mine every other year because of the limited miles I drive her, 56,000 so far.
When I do change the fluid I also use a chemical flushing agent, at half the recommended strength. Its very caustic and can burn its way through the freeze plugs when at full strength and done improperly. When mixing the anti-freeze, use distilled water only. The minerals in tap water are not good for your jeep.

If your not comfortable with replacing the t-stat and flushing it I would take it to a local radiator shop, not one of those quickie lube places. Ask there salesman/mechanic tough questions like how they flush the system, do the open the drain plug on the engine block? Do they use a chemical agent to strip the mineral build up? Do they regularly check there replacement mixture for the right mixture levels? Do they have a replacment pep-cock if it gets accidently broken off?
You have to be comfortable with your mechanic or service place. Once you find a place like that try to use them often and recoment them to all your friends. Good mechanics are hard to find.

I have a jeeping buddy who is a grad from Wyo tech, AA cert with 6 billion certs from just about every where, including Betty crocker school of cooking and auto mechanic(ok that was a joke). Scott (white XJ on my home page Pritchett canyon run) is my source for mostof my stupid and complex questions I have, he works at a local Big O tire, If I don't have the time, energy, or feel comfortable do something, Big O is where my jeep goes for all the work. Now I have to admit I dont pay alot there because the owner and Scott are also my trap shooting buds, but I always insist that I pay for any chemicals. And I constantly feed Scott and his wife dinners to pay for his time.
If you have one local, I recommend Big O just because I like there service practices.
 

Another good idea is to pull both heater hoses loose and backflush the heater core. The coolant travels the same direction (in one hose and out the other) for the life of the vehicle. Most sediment that won't pass thru the core gets hung up at the inlet portion of it. When you pressurize the core from the the outlet side and shoot water against the normal flow it will blow the sediment of "X amount of years" out the inlet hose. The older and lesser maintained coolant systems will really benefit from this and so will the internal cab temps. Use a garden hose and nozzle on the outlet hose and wrap a rag around the two to push the water thru the hose and avoid a shower. LBR
 
Back
Top