Search the Community
Showing results for tags 'transmission'.
-
K2XX Trans cooling concerns
Mwalabama posted a topic in 2014-2018 Silverado & Sierra Troubleshooting
Folks with the 159’ trans thermostat, over long drives does your trans temp still climb well over the 160 mark? I drove my 17 Sierra 220 miles today and by the end of the drive it had reached 180’ in 80 degree ambient temps. I would like to think the cooling system is efficient enough to keep it lower..?.. The condenser/trans cooler was replaced a while back, but this issue happened before that. Once I parked and let it idle, it dropped to 165 in 15 minutes. I’m not concerned right now, but I will be when it gets too 100’f out (Alabama weather, yay) and I’m pulling my boat to the beach or my other truck to and from the track on the flatbed. Do y’all think I’m missing something here and I have some issue? Or is this the standard and I need to just add an external cooler? When I first swapped the 159 thermostat( when the new trans was put in) the temps stayed at 145 all the time, but it hasn’t been that way in quite a while. I even pill flipped it and all that did was make it take forever to warm up but to the same effect. Full system fluid change was done about 1k miles ago with oem filter and ac delco dex6 fluid. Trans has around 47k on it. Truck has about 127k on it. Do y’all think I’m missing something here and I have some issue? Partially plugged line? Or is this the standard and I need to just add an external cooler? Any help would be appreciated at this point.. -
Hope nobody minds, but I'm going to start up a Quick Reference Guide for common parts/fluids/bulbs for the T1 HD trucks. I'll try to keep it updated if anything changes. If a mod wants to sticky it, I'm down for that too. Owners Manuals Chevrolet: https://my.chevrolet.com/content/dam/gmownercenter/gmna/dynamic/manuals/2020/chevrolet/silverado-2500-3500/2020-chevrolet-silverado-owners-manual.pdf GMC: https://my.gmc.com/content/dam/gmownercenter/gmna/dynamic/manuals/2020/gmc/sierra-2500-3500/2020-gmc-sierra-owners-manual.pdf Diesel Supplement: https://my.chevrolet.com/content/dam/gmownercenter/gmna/dynamic/manuals/2020/chevrolet/multimodel/2020-6.6-duramax-diesel-supplement.pdf Oil Changes 6.6 gas L8T (VIN code "7") Capacity: 8 Quarts AC Delco Oil Filter: PF63E / 19383806 Drain Plug Size: 12X1.75X18.15 6.6 Diesel L5P (VIN code "Y") Capacity: 10 Quarts AC Delco Oil Filter: PF26 / 89017527 Drain Plug Size: 12X1.75X18.15 Engine Air Filters 6.6 Gas: A3244C / 84121219 6.6 Diesel: A3248C / 84554703 Engine Fuel Filter 6.6 Diesel L5P: TP1015 / 23304096 Interior Filters Passenger Compartment Air Filter: CF185 / 13508023 Wiper Blades Drivers & Passenger Sides: 23387857 Spark Plugs 6.6 Gas L8T: 41-114 / 12622441 Glow Plugs 6.6 Diesel L5P: 68G / 12690238 Fuel Tank Sizes 6.6 Gas L8T, All Box/Cab Configurations: 36 Gallons 6.6 Diesel L5P Double Cab Long Box/Crew Cab Standard and Long Box Configurations: 36 Gallons. 6.6 Diesel L5P Double Cab Standard Box Configuration: 29 Gallons. 6.6 Diesel L5P Regular Cab Long Box Configuration: 28 Gallons. Diesel Exhaust Fluid Tank Capacity: 7 gallons Automatic Transmission Fluid 6L90 6 Speed MYD (Gas engine): DEXRON-VI Automatic Transmission Fluid 10L1000 10 Speed MGM/MGU (Diesel engine): DEXRON ULV Automatic Transmission Fluid. Transmission Capacities (Approximate): 6L90 6 Speed MYD (Gas engine) Pan Drop: 6.0 quarts Overhaul: 10.5 quarts Complete System: 12.4 quarts 10L1000 10 Speed MGM/MGU (Diesel engine) Overhual: 20.6 quarts Complete System: 22.08 quarts Transfer Case Fluid Electronic Shift Non-Autotrac MP 1625/1626–NQF: Dexron VI Electronic Shift Autotrac MP 3025–NQH: Dexron VI Transfer Case Fluid Capacities Electronic Shift Non-Autotrac MP 1625/1626–NQF: 2.4 Quarts Electronic Shift Autotrac MP 3025–NQH: 1.6 Quarts Brake System Hydraulic Brake System (Vehicles with DOT 3 brake fluid): DOT 3 Hydraulic Brake Fluid Hydraulic Brake System (Vehicles with DOT 4 brake fluid): DOT 4 Hydraulic Brake Fluid Wheel Lug Nut Torque All Models: 140 lb-ft / 190 N-m Front Axle 9.25" Axle Lubricant: 75w85 Synthetic High Efficiency Lubricant, 10-4091 / 19300457 Capacity: 1.9 Quarts Rear Axle 11.5" Axle Lubricant:75w90 Synthetic Lubricant, 10-4016 / 88900401 Capacity: 3.17 Quarts Rear Axle 12.0" Axle Lubricant:75w90 Synthetic Lubricant, 10-4016 / 88900401 Capacity: 3.17 Quarts- 25 replies
-
- 12
-
-
-
2019 Silverado 1500 z71 with 8K miles, 3.23 rear, 8 speed. Today I have towed about 8000lbs of cattle and trailer. I prior towed an old farmall tractor back. Both times when towing over 6000lbs, I had the transmission in L6, tow haul mode. Sometimes when taking off from a stop, it almost felt like the truck started in 2nd, not dropping down the first. Would it do that? Or is the torque converter just being floated as RPM's rise, and possibly I am not feeling the shift from 1 to 2. This transmission is crazy smooth compared to my 6 speed. Truck drives great otherwise. Ran it to town empty later, no issues. Even ran it thru the Low mode gears, and it starts in first normally. Thought maybe this was towhaul mode trying to avoid unnecessary shifting if still rolling. Transmission running cool, never over 180 even with that load at 60-70 mph. Thanks for sharing your experiences.
-
I have a 2014 GMC Sierra SLT 4WD 5.3L. 3 days ago while driving home I noticed that there was a slight stutter/shudder when the truck was attempting to shift up to the next gear. It seems that it only happens when easing into the gear at a slower speed,normally around 50MPH or so,and occasionally continues to happen while maintaining those speeds. 89,000 miles on it. I bought all the stuff do change the transmission fluid and filter but was hoping somebody could give me some alternative ideas to check before diving down that rabbit hole. Really needs this fixed ASAP, I’m a firefighter and this is my vehicle I commute to work in. Thanks in advance for any help. -
I have a 2020 RST with the 3.0 LM2 Duramax with 79k miles… the flywheel failed when I was driving down the highway and left me dead in the water.. I had it towed to the dealership 4 weeks ago and they called today and said the transmission and the engine needs to be replaced. Has anyone experienced this with their trucks? I never towed anything heavy and was religious with service.. luckily all covered under the 100k powertrain warranty… -
OK everyone I want to give thanks ahead for any advice and help. Truck in question= 2003 Chevy Suburban Z71, 5.3 L Transmission= 4L60-E So the story started when I was going down the road at about 50mph in cruise control, when suddenly I heard the engine begin to rev up. I hit the brake to take it out of cruise control and the engine stopped revving up. Apparently I lost transmission of power from the engine to the wheels because no matter what gear I put it into now, I get no movement from the vehicle. No reverse and no D1, 2 or 3. When I put the vehicle in park and attempt to push the vehicle it will not roll. When placed in any other gear I can then roll the vehicle freely. Before this happened: Since owning the vehicle 4x4 has always been shifty.....hehehe...sorry couldnt help it. I have the model where there are 4 buttons with lights the buttons are located left hand of dash near the turn signal. When I first got the truck sometimes it seemed like it didnt want to switch between gears. for example I would have to hit the button multiple times before it would switch and even then it seemed like it hadnt really switched but the lights would indicate it had. Most of the time the light for the button I selected would flash multiple times and then return to previous selection. Often times after turning the vehicle off and then returning to vehicle to go somewhere I would find that the light has switched back to a gear that it wasnt in when i left the vehicle. It seems to favor 4x4hi. As of lately I havent been able to get the lights to switch at all. It seems to be stuck in 4hi permanently. I have tested the 4wd switch and its fine. I tried unhooking battery for half hour with lights on to reset PC. I then reconnected battery cable and turned vehicle on but not start it. Then I pulled a bunch of fuses and plugged them back in. ( seen it in a video and the guy said it was supposed to wake up the TCCM) Well that did nothing. I have the truck off of all wheels right now and was trying to figure out if the transfer case is stuck in neutral. With the truck in drive as I turn the rear draft the front moves also. I am assuming that means it is in 4wd. But should I have someone hold the front drive shaft while i turn the rear drive shaft to confirm its not just from friction or something. I actually have the front drive shaft partly out right now in an attempt to get at and remove the shift motor and manually put the transfer case into 2hi. I am also considering changing out solenoids. I have gathered it is unlikely the shift solenoids. Is it possible it could be one of these: 1 * EPC (Pressure Control) Solenoid 1 * PWM Solenoid 1 * Manifold Pressure Switch 1 * TCC Solenoid w/Harness Another thing I suspect which would be an easy fix is the transfer case fluid level. I removed the fill plug and nothing came out. I can tell it has been leaking. I would have already topped it off but I have been stuck at home (no running vehicle lol). Could low fluid cause this issue? I hope that's all it is lol. Anyways I got a ride to the store tomorrow and to look at a back-up vehicle. Anything you guys recommend to grab from the parts store while I'm in town tomorrow? What would be your guys recommendation on how to solve this problem and fix it? All help is appreciated. thanks in advance, Aaron -
Were working on getting an 86 k10 back on the road. The trans slips between gears and doesn't have a working OD. Does this sound like a master rebuild kit fix, or should we be looking for another trans and just swap it in. I'm sure we could work through rebuilding it, but this would be my first time trying to fix one. Anyway, just wondering what to expect. Things like, how do you know if the pump is good, torque converter, any hard parts that could be broke that would save me the cost of the rebuild kit in case I just have to replace the trans anyway...etc... Thanks! -
I am currently helping my father with his transmission rebuild for the 4l60e on a 2002 avalanche, he installed a transgo 4l60e sk shift improvement kit along with adding a corvette servo. he installed a cam on the 5.3 and the engine runs flawlessly and for the transmission he added a 3000 stall converter. the transmission will shift into reverse fine and will shift into second with using the manual shift, however the transmission will not shift into drive. the valve body has been checked over and over again and everything seems to be in place. Has anyone else had this issue or know what may cause this? Any help would be greatly appreciated!
-
I noticed my transmission temperature getting quite high when driving on trails or towing through traffic so I decided to add a secondary Derale 13900 transmission cooler in addition to the stock front mounted cooler. My truck is a 2020 Custom TB with the 5.3 and 6 speed 6l80e. This kit came with everything I needed except for a couple fittings, and the fan is wired to an ignition power source so it won't drain the battery. You can see that it is mounted to a winch mount that I had made, but without the winch there that would be a great spot to fit the cooler. Essentially I followed the return cooler line from the transmission forward until the hard lines split off into two rubber lines with the return going to the driver side of the truck. NOTE: The hard lines are 3/8" but the rubber line is 1/2" (learned that the hard way). I first held the cooler in place and measured what angle it needed to sit at and tacked together some mounts, then after a couple of iterations got it to where it fit and the skid plate did not interfere. I then finish welded, drilled, tapped, and painted the mounts. On the cooler itself, I mounted the 180 deg thermostat to the lower connection. With the cooler location determined, I then measured and cut the 3/8" rubber hose in the kit. I then clamped the return rubber line on the truck, cut the rubber hose, and connected the 3/8" cooler hoses to the pre-existing 1/2" hose on the truck. I used one 3/8-1/2 straight barbed connector and one 3/8-1/2 90 deg barbed connector. Some zip ties to tidy up the lines too. Wiring was simple as well, easiest way to get a for sure ignition power source was to get a fuse tap from autozone for a micro2 fuse and then you have a fused ignition source. Ran the power to the thermostat and then positive from motor to the other side of thermostat and the ground to the frame. The hole in the skid plate has an aluminum mesh behind it to keep small rocks out, and it's pretty high up so shouldn't see much abuse. Haven't given it a full test for cooling capability yet but the fan is nice and strong so I have no doubt it'll help. For about $200 total I'd say its a great upgrade for anyone who tows in the city or hits the trails on any steeper terrain.
-
I have a 1988 GMC G3500 Vandura Box truck with 350 5.7L TBI. I am renovating it to be an RV. bought new motor and had a mechanic I know and trust do that and a bunch of other stuff. It drives great. Runs great and shifts great; EXCEPT when I need to down shift to pass another vehicle or going up a mountain here in West Virginia (and there are allot of them, lol). My son is a mechanic but in Alabama. I texted back and forth and he mentioned the things I put as tags. TPS, modulator and adjusting the TV cable. I have the service manual and two other manuals. Anyone else have the same or similar problems? I downshift by using the shifter on the column. any help is greatly appreciated. email is: [email protected] -
2017 1500 SLT, 52kmiles, stock other than GM/Borla. Truck is never used for towing, but is my daily driver. I noticed recently there is an "odd" upshift between 2nd and 3rd at random times. Usually after driving for a while. Took it in to the dealer who says all is good, no burned fluid and can't duplicate the issue--they say they took it up to ~190. I drove the truck about 470 miles this weekend on vacation after dealer cleared it, but monitored the tranny temps more closely and noticed on the long highway drive with minimal cargo/passengers temp is sitting around 225-232. Ambient temps in the upper 90's. This seems high to me with very little load, but I never really paid attention to temps prior to the shifting issue... so no baseline to compare to. What temps are expected/normal?- 8 replies
-
- 1
-
-
- temperature
- 6l80e
- (and 2 more)
-
John Goreham Contributing Writer, GM-Trucks.com 4-25-2019 Back in December, GM-Trucks.com member Jammin87SS posted a note here about a class-action suit related to GM 8-speed automatic transmissions. This transmission was used widely by GM, including in the Sierra, Silverado, Colorado, and Canyon pickup trucks. Owners have been complaining of shuddering and hesitation. Owner of a Silverado, Ed T., wrote a typical description for CarComplaints. He says, "Ever since I bought this truck new there has always been a shifting problem. This problem occurs whenever I slow down to a fairly low speed and then accelerate. When I accelerate there is a hesitation for a second or 2. This is very annoying and could potentially be dangerous. I have contacted my dealer and he just says "that's the way they shift, no fix"??? Dealer also stated that the transmissions have a learning chip and shifts the way a person normally drives - that's total BS. I have had my truck for over 2 years and it still shifts poorly. Besides the above I love my truck very much, GM just has to fix this problem..." GM knows there is a problem. It has issued both notices to its dealer's technicians and also TSBs. However, it has yet to find a solution that works. There is a class action suit that you can learn more about here. Our questions for our members are; 1) Have you experienced any issues with your 8-speed, and 2) was the dealer able to fix it? Let us know in the comments below.
-
Hey all, 2017 Silverado, 5.3/6spd. My transmission issue only happens when I first drive the truck for the first time in the morning. The truck has to have been sitting overnight for this to occur. After starting the truck and driving, the trans will "fish bite" or stutter when shifting from third to fourth. It will do this once, (maybe twice) and be good and problem free for the rest of the day. Has anyone else experienced this? It only happens when the truck is first driven after sitting overnight. It's not really a major issue, as it doesn't happen again after the first time, but it's pretty annoying. This issue only occurs at light/part throttle, and my speed is around 25-30 mph. I do not notice any variances on the tach while this happens. Also, if I drive with more pedal/throttle, I will not experience this stutter. I spoke with the dealer about this when I went in for my second free oil change, and they could not replicate the issue. During my first trip to the dealer, they downloaded a program update for the transmission. It helped overall, but the isolated problem is still present in the morning. I have read somewhere on this forum, that this was a "normal" occurance, and attempts to remedy should not be attempted. I believe that post mentioned that transmission fluid temperature played some part in this. Any ideas or input? Thanks in advance! Steve- 38 replies
-
- 1
-
-
- transmission
- chuggle
- (and 1 more)
-
2017 Silverado LT 5.3 4X4 6speed transmission 51,000 miles When I first bought the truck the transmission suffered from severe bucking or shudder under light load. GM calls it chuggle. The cause was "intermittent tcc delamination causing scoring on fluid pump". They replaced the torque converter, cover housing and pump cover along with a flush. This was at 10,000 miles. That seemed to solve the chugging problem. For the last year or so I have noticed that the torque converter unlocks and locks frequently at freeway speeds. When it locks, following an unlock, there is a noticeable lurching forward. This is not neck snapping but is definitely noticeable. This lurching motion also occurs when upshifting 4/5 or 5/6. While driving at freeway speeds (65 70mph) when I slightly let off the accelerator the rpm's rise about 200 then settle down. If I should slightly press down the same thing happens. However, when driving at a steady freeway speed, and holding steady on the throttle, on level ground I can feel this unlock/lock along with seeing the engine speed move up then settle down. If I engage cruise control on level ground it is worse and occurs more often. But, with cruise control on and there is a slight road incline there is no unlock or downshift. When I press hard on the throttle then it downshifts and accelerates fine. Locking/unlocking and lurching; I do not recall the transmission behaving like this in the early years. The dealer says if it doesn't throw a code then it is operating normally. I can see that there are times when it should unlock such as when under load, but should it be this happening this frequently and be so noticeable? Or maybe I am being too sensitive? Anybody experience the same thing? Is this normal transmission behavior? -
Anyone know what this noise is? It's very intermittent. Seems to do it most often between 40 and 50 MPH cruising with maybe a slight up hill. Never does it on coast or heavy acceleration. Very hard to tell where it's coming from. 20190521_191545_001.mp4 2014 Sierra Denali 1500 Crewcab, 5'8" bed 6.2 Litter 3.42 axle ratio about 118,000 miles- 5 replies
-
- 1
-
-
- drive line
- noise
- (and 12 more)
-
My 4l60e is starting to show its age a bit. Not ready to condemn it yet but it occurred to me that it would not be too difficult (on the scale of trans swaps) to put a NV4500 from a GMT-800 HD truck in place of my 4l60e. I've done a bunch of research on which part numbers I would need and it seems mostly manageable but I have run across something I can't find the answer to online. My NP246 transfer case has the 27 spline input shaft because it's currently hooked up to a 4l60e. The NV4500 has a 32 spline output and was never (as far as I can tell) offered with a NP246, just the NP261 it seems like. However there's a part number for a 32 spline input shaft for a NP246. If I install that input shaft, will I be able to put my NP246 behind a NV4500?
-
Hello everyone, Well I took my 2014 Chevy Silverado 1500 up to the dealership yesterday for transmission issues. When accelerating around 30mph the transmission makes a high whining noise around 2000 rpm almost like its slipping and the truck shakes back and forth. Then when on the interstate on cruise control around 65-70 you will hear a grinding noise every few minutes. Also when you slow down from the 60-70 mph range to around 30 mph and accelerate the grinding noise becomes more apparent. When I dropped the truck off yesterday I showed the service guy video of the grinding as well as what I believe to be slipping and he said "Yeah that sounds like it is slipping". Received a phone call this morning from the same service technician saying they were not able to replicate the issue. That the transmission guy said that is normal when it switched between V4 and V8 mode. It's amazing I have had this truck and driven it for 76000 plus miles and have never heard that whining or grind noise. I asked how long they test drove it and he said 10 minutes. I told him they need to drive it around longer and actually go on the interstate to hear and see what it is doing. This is not the first time I've taken my truck up there for transmission problems and I am not picking this truck up again until they find the issue. The first time was for rough shifting to which they said was normal. This is my first Chevy I ever have bought or owned. Bought it brand new from the dealer. I must say that with how I keep getting treated with the "can not replicate" issue as a scapegoat for not truly trying to satisfy the customer is getting old. Especially being I have videos in which you can see the rpms and hear the whine up and hear a grind noise. This will most likely be the last Chevy product I purchase. If anyone has any ideas and doesn't mind listening to the videos I have I would appreciate it. I will have to post a link to youtube since the video will be to big to post here. Thanks -
Has anyone else used the AMSOIL OE ATF over the Signature Series in their 8 Speed? Any issues? Looking to get a flush done soon and want to make sure the fluid is compatible. I'd rather not shell out $300 CAD for the signature series when the OE will do. Thanks. -
Shifting on interstate
Daniel Johnsey posted a topic in 2014-2018 Silverado & Sierra Troubleshooting
I have a 2015 Chevy Silverado 1500. Yesterday driving down the interstate with cruise control on I noticed the truck shifting back and forth between fourth and fifth gear. It seemed to hold fine when I would take the cruise off and hold the speed myself. It would also stop when pulling a hill as it would stay in fourth gear. Today it seemed to be doing the same thing in the lower gears and the check engine light came on as well. Planning on hooking it up to the scanner tomorrow but am looking for any ideas of where to start. -
I am looking to replace my sensor and the harness as they are known to be bad and causing the p0711 code. In my research I found the 2015 has a split harness but they changed it in 2016 to a one piece harness and then I believe they went back to the split one, not sure which year. What is the part number for the sensor and harness? I've looked everywhere and can't find nothing, plenty of threads but noone has mentioned part numbers and acdelco website does not have a part listed in their catalog for that year.. nor does any parts site like napa or autozone -
Just curious if anyone has the same issue I've been having. So on the very first shift of the day from 3-4 my trans seems to slip into gear. After the initial run through the gears it shifts great every single time after that. I have real basic stuff done to my 14 Sierra..cold air intake, cat back exhaust and blackbear tune (yes the trans was tuned). It really seems to be temperature related because it gradually got worse the colder the nights get (I live in the northeast). And no matter how long I let the truck warm up before I drive it, it does the slip but only 1 time. Not sure if this is also related but the tuner said the torque converter locks after the shift into 4th gear.
-
Hi All, Newbie here in the forum.. Vehicle: 2021 GMC Sierra 1500 Denali I took the truck to the shop for 3.5 inch lift, earlier. The guy who works there said if I lift my truck, GMC is going to void my entire warranty. I wonder if this is normal? I was also told that most of the lifted trucks have transmission oil leaking issues, so I will need to install a front differential drop kit. Does GMC has such issue for only 3.5 lift? Thank you guys in advance! -
So up until yesterday the truck was driving relatively smoothly, there was the occasional hard shift from 1st to 2nd (which I believe these trucks are known for). I stopped at a stop light yesterday and started going and then at about 20 MPH the truck decided it didnt want to shift. This happened a few times throughout the day and seemed to get worse as the day went on and at this point it now does it every time it gets down into the lower gears. I switched to manual to see what gear it was stuck in and it showed 2nd and then 3rd after it shifted and didnt want to shift up. EDIT: Transmission temps when I was looking did not appear to get above 205 F, Fluid is red like it should be, level seems fine. Is there a known issue with these transmissions or an easy fix I can attempt? Transmissions are voodoo to me -
I have a 2019 Silverado LD with 21k miles on it. I noticed that if I'm in manual mode, I get a hard downshift from 3-2. No other gears. It does it off and on. What could it be? -
Bear with me, this is a long post, but I've been troubleshooting a bizarre intermittent transmission slipping issue and potentially a related electrical issue. Any thoughts/theories would really help here. Just to note, the two shops, Shop A and Transmission Shop B have a reasonable reputation in my area. Vehicle: 2004 Silverado LS 1500 4x4 Ext Cab Short Bed, 111,000 miles (daily driver until 2016), 3,000 miles/year since then. Owned since new, this truck has not lived a super hard life. Symptoms: 1) Initially had intermittent slipping in 1st gear, either in DRIVE or manual gear selection in middle of June 2) Continued to slip intermittently after transmission fluid/filter replaced July 6th 3) Check engine light (code P0758 ONLY) appeared late August, would not go into 4th in DRIVE and slipping in 1st gear again (in both DRIVE or manually selected). 3rd gear on highway works fine. Manual selection of 2nd and 3rd seems to be okay to get around. 4) Solenoids A and B replaced by Transmission Shop B on Sept 3rd 5) No obvious power drains EXCEPT on the IPC/DIC circuit which was about 200 milliamps 6) Previous battery draw issue over the previous 2 years. Usually would kill a battery between 12 and 48 hours. Very intermittent issue. 7) Recent wet day battery draw issue reappeared. Actions taken so far: 1) Fluid and filter replaced by Shop A on July 6th a. Worked for one week, slipping issue reappeared intermittently throughout August 2) Solenoids A and B replaced by Transmission Shop B on Sept 3rd and solenoids tested with independent power source, functioning properly. a. No change, Check Engine Light still illuminated with code P0758 3) Checked all fused circuits on Sept 4th a. One drain on the IPC/DIC circuit of about 200 milliamps Working theories (in levels of severity): 1) Possible gauge assembly short due to the IPC/DIC circuit drain possibly related to a transmission control circuit? Seen this pop up a few times on other forums, but I am doubtful, then again, this was early 00's GM where fog light fuses did not match with the fog light circuits... 2) Short on the transmission harness 3) Short between the PCM/ECU unit in the engine bay and the transmission harness 4) Bad PCM/ECU unit <-- This is my top theory considering the connectors are oriented sideways and have dirt/debris all over, combined with a wet day may result in a small short causing both the transmission issue AND the battery draw.
