deehammer

The shaft for the Blender door was not aligned correctly. Had to pull the entire HVAC Box again. I feel like I am an expert at it now took me about 90 minutes. Mike mentions it on his video but you have to make sure that the Blender door shaft is aligned to the other side of the box. Before installing everything I hooked up the power and tested it out to ensure the shaft moved back and forth. You can see the movement from the top of the HVAC Box by looking at the pin. @dripley yeah I checked the coupler as well while I had it taken apart it looked good. Thanks to all for the advice on this project. Took a total of about 12 hours (without my rework) which included the following being replaced: New Dash From LMC Truck...seriously I could not imagine a part fitting better this dash looks, feels and fits great. The screws from the backside were the hardest part of everything I did. Heater Core I have pictures of my old one that I will post dang that thing was not in good shape. Also put on new heater hoses the old ones were not worth saving as they were stuck on so bad I just cut them off. AC Evap at least 30% was gummed up with dirt and crud. Blower Motor and Resistor because I felt like it. Overall it was not a terrible job. I got to know my truck a little better and it looks and functions so much better!!! Below are some pics not really in any order but I thought some might like to see. If anyone has anything specific they would like to see let me know I have quite a few pics. Also if anyone is in need of advice I am pretty darned schooled on how to do this job now!!!

So I got the job done. Really not horrible just time consuming. There is one issue though....I cannot get any heat. All vacum lines seem to work (changes from floor to dash to normal) fan speed works fine just no Heat. The new Heater Core gets hot like it should no problem. I am thinking it is probably something I did but am stuck in that "everything went just fine" haze right now. I do not have the A/C system recharged at this point but that should not cause an issue. I am guessing the selector switch from Heat to Cold is not functioning properly and even though I had the HVAC Box out today I do not know exactly how it works. Help me out here guys in need some advice. Would really like not to pull the HVAC Box again but I will do what I have to....Thanks Further investigation on Mikes article section revealed a quick video about the Blend door. The motor "operates" when moved from hot to cold and then visa versa. I can hear the motor run for 5 seconds or so after switching back and forth. Arrrggghhhh I am thinking I need to pull the HVAC Box again. Maybe I did not put something together correctly after I had the box split this morning. I remember everything lined up correctly but maybe there was something that I missed like the darned blend door shaft being aligned which I can no longer see thanks to the the new Dash isntalled . Thanks again for any advice.

Ok everyone I have the parts coming in Today and Tomorrow to replace my Heater Core. I am also going to swap out my Evap and Blower motor while I have the HVAC Box out. To top it all off I have needed to replace my Dash for awhile now so one is on the way from LMC Truck and that will be going in as well. Mike I have seen your video on You Tube and it breaks things down pretty well for the HVAC Box. If there are any little tid bits or pieces of advice anyone has please share them with me. I will write up a synopsis of how the job went when I am finished. Thanks Probably should have put this in 2nd Gen Non Powertrain Related if someone can move this that would be great.

Knock on wood but I have 255k on my original VP44. Also I still have the stock lift pump and filter setup although I am on my 4th lift pump. I have always had a mechanical fuel gauge installed so I am religious about swapping filters and pumps when they go bad. The earlier manufacturer of the lift pump seemed to make a bad quality product never could get over 15 psi and 6-8 at wot also I remember them costing $150 or so. The last couple are a newer design that get around 19 psi and 12-14 at wot, plus I picked up the last one for $80. If/when I replace the VP44 I will look into an upgraded pump and filter setup. Just my experience and yes I know for the cost of all my pumps I could have gotten an upgraded fuel system already!

As far as where to buy the non greaseable spicer u joints I picked them up at a local six states shop best deal I could find and they had plenty of them. If you do end up having to change the bearing I would recommend using Timken. Btw for what it is wort the power steering method popped mine out very easily sorry to hear it did not work for many of you.

Hello to the board. I have already posted a couple of times elsewhere but I thought I would introduce myself. I have been reading through posts for sometime now as well and just want to say thanks for all the info I have learned here. My name is Dave I am originally from SLC UT, I currently live a few miles north near Hill AFB. I am a Computer Science Major working as a Software Engineer. I am also in the Air National Guard and have been in the Air Force in one form or another for 19 years which is also how long I have also been married to my sweetheart (wife not my truck). We have 6 kids, ages 18 to 11, and yes it has been hard to watch my two oldest learn to drive a stick on my baby (my truck this time). I bought my 99 Ext Cab, 5 Speed completely stock 24V in 2003 at just under 100K miles. Currently sitting at 250K. It is the dreaded 53 block but I have not seen an issue yet so I consider myself lucky. I drive my wife a little bonkers as I am always reading up on or watching videos about my truck, which usually leads to me spending more money. She doesn't mind much as her Honda Pilot gets just as much care by me as my truck does if not more. I tow the 6 ATV's on a flat bed trailer around 5000 lbs. No major modifications have been done that would make anyone salivate. I did however install gauges fuel (mechanical), pyro and boost immediately after buying which has allowed me to watch for the common problems. I love to tinker in the garage so between the 6 ATVs, the 99 Cummins, 2004 Honda Pilot, 2007 Honda Pilot and a 2006 Ford E-350 12 Passenger Van, I have plenty of opportunities. However I consider my truck to be more of a hobby. When I shed some of the chitlens, increasing the pocket book, I plan on putting a 4BT in a restored/updated 1979 Ford Bronco with a NV4500 manual in honor of my Father. Thanks for reading.

@ leathermaneod I would do it myself like explained above (well I did) and save money. Anything can expose or cause leaks but if it does it was probably time anyways. I have a small heater core leak right now that is probably due to it being 17 years old/250K miles and father time taking its toll.....not the flush. My opinion. Good luck.

Mike wrote this article up awhile ago... https://mopar1973man.com/cummins/articles.html/24-valve-2nd-generation_50/51_engine/cooling/ Pictures can be a little confusing as Mike flushed the Engine through the thermostat housing but he states this pic is different....if you read carefully on what he wrote it basically says: 1. Drain Coolant 2. Remove thermostat housing, remove thermostat and but thermostat housing back on 3. Remove the other side of thermostat housing hose (the one going to the top of radiator) 4. Point this house out the front of the truck 5. Remove radiator cap, put garden hose in and turn hose on full 6. Start truck and let run for 5-10 min or whenever clear. 7. Put new thermostat in put hoses on 8. Fill with Coolant/Water (your choice on coolant or distilled) I used Supertech full strength and distilled water approx. 3 gallons each. Many odds and ends steps missing but it is a good write up.

Exactly what I did.

My 99 has rear drums. I looked into putting a Disc upgrade kit on the rear end however the cost as well as lack of good emergency brake left me just upgrading the rear Cylinders to the 1-Ton Chevy ones ($8 apiece), replacing all hardware and new pads/drums last time I did the job. Should last a good while and it gave me a good opportunity to teach my sons what a real brake job looks like!!

@ unioncreek I appreciate the advice however I am going to evacuate the system and replace the Evap while I am doing the job. This allows me to pull the entire HVAC box as well to clean, lubricate and inspect.

I am convinced it is the heater core at this point. Had the temp setting on cool for about 10 min or so (at full temp, no blower on) as soon as I moved the tem setting to hot instant vapor for about 10 or so seconds with the sweet scent of coolant in the air haha. It is not a big leak so I am going to do some research and then order a bunch of parts before tackling. Mike I have seen your instructions as to how the dash is moved out of the way and I fully agree with the advice of pulling the entire system to clean it out rather than hacking in just a new heater core. I have a couple of questions you all may be able to help with before I dive in, as the engineer in me will not tackle things until I know fully that I have all knowledge/tools available to me. 1. New Dash: I have done some research, it looks as though the LMC Dash is the best value for the product. Does anyone have a different/similar opinion they would care to share? 2. AC Evap: Two things here how tough are the AC lines to the Evap to get off? Special tool needed at all? 3. AC Decharge and Recharge: How much does this cost to do have a professional evac the system and later recgarge? This is something I have never messed with. To be honest it makes me nervous to even touch my A/C system it has ran like a champ for over 14 years. Any advice in this arena would be helpful.

Yeah I played with the cold setting a little bit and it ran fine. I will set it to cold first thing in the morning to see how it reacts. Thanks for the responses so far.

I have used the Sealed OEM Spicer U-Joints the guys I talk to at Six States locally here have said they recommend them over the greasable ones. I just did my rear drive shaft ones and they are what I used. Seemings how the OEM ones lasted around 250K I felt good about going this route.

I live in Utah not really humid here at all, days lately have been in the mid 70's with lows in the 50's. It is really odd I know. I need to replace my Dash in the near future it is in shambles I have been putting it off so I am thinking of doing the Heater Core, Evap, Blower Motor and Resistor while I have access in there. I know these items cost but when in Rome......

There is not much smell to it like I said it is not very much vapor at all...smells a little musty most definitely not smoky that is for sure. Cab does not have the strong sweet odor a larger antifreeze leak would give off, I know what you are asking.

New to the site here so be patient with me. I have been wanting to join this site for awhile so this is as good an excuse as any. The last two mornings I have seen what looks like vapor/smoke coming through my A/C or Heater vent. It is very light and almost unnoticeable but it drives me nuts. It only lasts about 15 seconds or so and is very light. It does not have a smoky smell it is more of a light musty smell but it is very faint you have to get your nose directly in it. Comes on when the truck is fully warmed up at 190 degrees. My blower motor is not on at all the heat dial is set to heat. When I drive throughout the day the problem never happens again. I think it is a small leak in my heater core that when my truck gets up to temp it vaporizes through the vent. I do not have a noticeable leak in the heater core (aka no antifreeze on the passenger floor) and my coolant level has not dropped noticeably. No overheating issues. A little background...about a month ago I drained and flushed my Cooling system per Mikes directions on this site. Prior to the flush I was not getting my temp over 160 degrees which turned out to be a bad Thermostat. Now I am getting around 190 degrees constantly it has been nice to have real heat. My thoughts are my Heater Core may have been doing this for awhile which I never noticed or never vaporized due to not reaching temperature, or the flush jarred something loose (hadn't changed my fluid in 100k miles don't throw stones). Just wondering what you all think, I feel I am pointing in the right direction. Don't know how to add my Vehicle info on here yet so here is a quick rundown of what I think is important: 1999 Ext Cab, 5 -Speed, 250 K Miles