When you purchase through links on our site, we may earn an affiliate commission, which supports our community. Re: Allison problems. This transmission has received high praise as it does work very well when it is in tow/haul mode. Using tow haul mode fixes that problem. In this article, we intend to discuss some of the reasons for the hard shifting problem in the Allison transmissions, along with their simple solutions. Vehicle lunging forward. But there are so many other red flags to look out for. The problems can be overcome and one should not avoid this transmission because it has problems. These conditions are usually a result of the Transmission Control Module (TCM) receiving incorrect inputs from onboard sensors. For example, someone who has a lead foot will see later upshifts across normal driving conditions than someone who does not. It is at about 550HP that the LML and above input shaft begins to die, but approaches 600HP safely in the earlier years of DuraMax. There are a lot of concerns about the Ford 10-speed transmission problems. Unfortunately, a driver can't reverse limp mode. Added power problems- due to the design the transmission is only built to handle so much power. Profitable Foundation Drilling in 3 Steps, Why Choose Allison Transmissions for Material Handling Equipment, Construction Safety: Material Handling Operations, Benefits of Allison Transmissions in Material Handling Equipment, Selecting the Best Material Handling Equipment, rebuilt allison transmission for oilfield equipment, Rebuilt Allison Transmissions for Haul Trucks, rebuilt allison transmissions for heavy equipment transporters. Time will tell if these problems are as bad as the car experts claim. Some common signs that you have a bad transmission module are, a dramatic change in your fuel economy, constant transmission solenoid trouble code even after replacing them, constantly experiencing shift lock or random shifts and getting stuck in neutral when shifting. Bear in mind that thanks to the function, it gets locked . 6 Causes of Manual Transmission Hard to Shift (Especially 1st to 2nd), 7 Symptoms of a Worn or Bad Clutch (& Replacement Cost), 3 Symptoms Of A Bad Tire Pressure Sensor and Replacement Cost, 5 Reasons Why Your Brake Pedal Goes to the Floor, How to Check Automatic Transmission Fluid, Transmission Fluid Color Chart And What Each Color Mean, 6 Causes of Transmission Fluid Leaks and Repair Cost. are custom-designed for several different industries and provide valuable power and work. Some of the most common signs of transmission control module failure include trouble shifting gears, getting stuck in gear, and lower gas mileage. The magnet does pretty good in the bottom of the pan, but it doesn't catch it all! The problem lies with the Torque Converter Lockup Mechanism and not only does it happen at that HP level, but it will also have problems when truck owners change their tire sizes to larger versions without a re-gear adjustment. This was so we could compare our testing results when it warmed up and started having the flared shifts. Between second and third gear it seems to be shifting slow/hard(?). If your automatic or manual transmission is shifting hard, don't panic. Copyright 2023 Mechanic Base. At the same time, the dashboard lights will illuminate. He felt like this could be a blown seal or a cracked C3 piston because hes seen it before. CamperUpgrade.com is a participant of the Amazon Services LLC Associates Program, an affiliate advertising program it is designed to provide an aid for the websites in earning an advertisement fee by means of advertising and linking to Amazon.com products. Unfortunately, a driver cant reverse limp mode. This mode is triggered by anything that could cause severe damage to the transmission, including severe overheating or towing a very heavy load. Next thing will be a limp. Spartan Chassis vs Freightliner: Whats The Difference? Transmission is one of the most expensive components, and attempting to repair it on your own can damage it even more. This is a common platform in 6 speed transmissions. It was announced in 2019, that the 2020 Sierras and Silverados would be coming out with this transmission option. I don't keep track, but when I was new on other forums, I had some real newby questions too. The Valve Body- it can wear out fairly quickly but there are no regenerative options available. The issues can be serious in nature and expensive to repair. Problem #2 - The Valve Body Allison valve bodies are notorious for one problem in specific, valve seizure. Jun 1, 2011. Our Transmissions 101 on the Allison 10L1000 can be found here. High transmission fluid levels and a failed vacuum modulator may throw fluid out in an Allison transmission. If your transmission is installed in an older vehicle, check the vacuum lines and other parts connected to the transmission. The most common causes of manual transmission shifting issues can be caused by faulty gears, a defective clutch, low gear oil, a damaged synchronizer ring, or a bad gear hub sleeve. No doubt, a transmission plays a key role in the proper functioning of your motorhome. Our testing was straight forward. The manual transmission also requires fluid to keep the gears lubricated and running correctly. The unit was introduced as a 5 Speed, despite having the ability to employ a 6th gear. Operator selection that is an input via the selector cable and positions the selector valve. Get it replaced immediately to prevent the fluid from leaking. The Allison 1000 Transmission Oil Pump is generally reliable, but begins to lose efficiency very early in life and its struggle to produce pressure quickly begins to scale as it ages. if its the converter clutch, could it just need a new converter? An Allison Automatic uses the full torque from the engine and multiplies it with the torque converter. This mode is triggered by anything that could cause severe damage to the transmission, including severe overheating or towing a very heavy load. The customer agreed to the repairs and understood the situation. On your vehicle, probably a vacuum modulator. Many Allison Transmission users have reported that their device is not shifting properly. The transmission vacuum modulator valve is responsible for measuring the load from the engine to provide ideal shifting operations. http://videos.streetfire.net/video/23f2b2fe-19c6-4d23-8aa3-7c901af66a77.htm, http://videos.streetfire.net/video/Rodo-du-Camion-2007_170272.htm, http://www.youtube.com/watch?v=9J5PHwZIZ0g&feature=related, http://videos.streetfire.net/video/Is-this-the-best-drift_89700.htm. you feel the cooler lines and the pan with you hand it is not over 180. replaced PSM flushed coolers, no change to issue. This will give you accurate readings. Powertrain Expo Owners have stated that in the tow-haul mode it is a solid transmission that tows at least 9000 pounds with ease and without causing any trouble. When the founder died 14 years later, GM bought the company and made it one of its subsidiaries. This will shorten its lifespan. This indicates that the oil has gotten old and you should replace it. Line pressure was good, no codes have been set in any system, and no abnormalities with any sensors on the scan tool. If you have an Allison Transmission in a GM Truck from the mid 2000's there is a service bulletin for the TCM module . 7200 Ertel Lane The customer agreed to leave the vehicle, which is where my opportunity to get involved came in. This also goes for using the wrong fluid for your transmission system. You can then check all of these connections and correct them if you notice any errors. There could be many reasons for this problem that we have mentioned in this article. Allison shift valves are very long with many different lands along them. The OEM Oil Pan- there are numerous problems with the design since it is stamped and then cooled. Certified Automotive Diagnostic Technician. RELATED: 7 Symptoms of a Worn or Bad Clutch (& Replacement Cost). Directly oiling the C3 clutch pack is a critical improvement to this transmission that allows us to encounter this transmissions maximum potential. No one looks forward to resolving transmission problems. An input shaft to output shaft speed ratio of 1:1 (often 4th gear) is known as direct drive. 6. It can wear out very quickly and needs to be made out of steel not aluminum. We were confident that it was not a computer issue, and that it was time to do further inspection. This is just one weakness that comes with this transmission and we will get to those later. Now it happened again last week and it wont move at all and the D just flashes. You might see this show up most commonly when shifting between first and second gear. 5. It is often associated with insufficient transmission fluid. We discuss the possibilities of what is causing this problem. So far no one we have read on the discussion forums has mentioned this problem so they may not reach those levels or make those changes. Magnus is the owner and main author of Mechanicbase. dealer refuses to address. Check out this 2020 Mack GR64F For Sale on RockandDirt. (Data Link Troubleshooting), 10 Speed Allison Transmission Problems and Review (Any Good? 5 Common Flexsteel Recliner Problems (Troubleshooting), Want More Room? Then it is recommended that you take off all the vacuum lines completely. If you disconnect the battery or theres another type of fault, the adaptive transmission could fail to use its memory settings. However, if you drive on muddy terrains, you may need to replace it more frequently. In fact, when we cut the converter apart to begin manufacturing our popular Allison Torque Converters, we often see 6 distinct burn spots over the pads of the cover where the bolts thread in. The transmission fluid becomes thicker as the temperatures drop, leading to less lubrication. Dealer service writer and other mechanics state problem is very common and part should be recalled. Houston, Tx 77040, Phone 713.466.9838 Moreover, consider investing in a quality transmission fluid that can maintain its properties during winter. The hazards: a reaction carrier is part of the transmission rotating assembly and is an important aspect of its operation. Until the transmission reaches its normal operating temperature, the operation could be rougher than normal. I don't think so. One solenoid controls the apply rate of one clutch, while the other controls the release of another clutch. It would take a day or two then the check engine light would go away. As a result, you could experience rough shifting while the transmission relearns the proper operation. Lack of air supply, leaking air lines, malfunctioning check valves and a sticking pressure regulator valve are probable causes of a faulty retarder. (That is what Allison calls it when the engine rev's before the 3 to 4 shift is complete ) It will also do it going from 4-5shift. An automatic transmission can shift hard, jerk or hesitate for a number of reasons. The problem was significant enough on some 2012-2013 Ford F-150s to cause Ford to issue a technical service bulletin (TSB 13-1-10). 2001 GMC 2500HD ec/sb LB7 + Allison 5 speed this video is pretty cool: As the valves travel axially over time, they slowly damage the bore similar to a piston traveling in an oscillatory fashion through a combustion motor. The Allisons central pump gears work similar to how most engine oil pumps work; two gears, one residing inside the other. Allison transmissions work smoothly most of the time, so there is definitely something wrong when you experience hard shifting. The dipstick has marks for a reason. Since the transmission fluid lubricates the clutch and gears, they will likely get stuck when there is not enough fuel in the system. They just need to be fixed or redesigned so that the transmission work is even better. All Rights Reserved. Still have reverse but when I went to back it on trailer I lost reverse shut truck off started it had reverse again. It is a complicated system that has little room for error. One common problem will be the shifting aspect. This forum is still pretty new, so there isn't a whole lot you can do a search on. We could have rushed to pull the transmission, but the oil was clean, and there wasnt any debris in the pan. They also stated if anyone ever needed any transmission work done, they would refer them to him for his honesty and hard work. After that you may run into difficulties including a transmission lockout which many car experts think should not take place. If your gears aren't synchronized properly, it won't shift gears smoothly. When the input shaft to output shaft speed ratio is below 1:1, the tires will rotate less times for each revolution of the crankshaft, multiplying available torque at the expense of top speed. But things may go wrong rather unexpectedly. Thanks. The only way to prevent the system from overheating is by installing a cooler on it. This transmission is a vast improvement over earlier models and those were said to be good as well. You might also get the same issue which is why we will be using this article to provide you with some troubleshooting steps. Besides, the impurities can also cause serious damage to the transmission system. However, you may actually be experiencing a failsafe instead. These products have amazing features on them and there is a huge lineup to select from. Numerous "Attempts" via TSBs and cover-ups by General Motors has failed to . Allison was a GM company for decades so this new transmission should still be good even though GM spun it off recently. Oh yeah , change the filter, i change mine every other oil change on both trucks, thats 7 k on mine and 10 k on the wifes! But in this case and for this transmission, GM is taking on the responsibility of building this transmission. Those are electrical communication trouble codes. One thing about this sell off is that GM may have kept a portion of the Allison company for itself. Allison shift valves are very long with many different lands along them. 3. Many Allison transmissions have a common problem, and the 1000 series is no different; oil does not adequately reach the C3 clutch pack of the transmission. However, if you see dark spots on the surface where your motorhome is parked, you could well be dealing with a leaky transmission fluid reservoir. We bought a 1998 American Eagle, Allison 6 speed transmission, Cummins 350hp and had the same problem with the DO NOT SHIFT message. The P2 Planetary operates synchronously to the C2 hub and also synchronizes in speed with the input shaft during the 3-4 upshift. Copeland International, Inc. . Without further ado, well jump right in! 2016 GMC Sierra. We found almost no difference in the commands to the trim solenoids from cold to hot. If they do, you are free of this problem, if they dont, its time for one of our Allison 1000 Valve Bodies. The torque converter is filled with transmission fluid and therefore poor transmission fluid can make the converter behave strangely. Inside the transmission, gears are working hard to create a smooth ride. NisswaDoc. If theres anything out of place, switch them back and try again to see if you can duplicate the problem. The most common reasons why an automatic transmission is shifting hard are due to transmission fluid issues, a bad transmission vacuum modulator, a failed transmission sensor, a bad shifter cable, or cold weather. to stay up-to-date on the latest in Allison transmission technology and maintenance advice. The Allison 10L1000 can only handle up to 500 HP. Free 800.966.9860. He drove the customers vehicle, and sure enough, it had a slight flare on the shift from second to third, and fourth to fifth. This is because impurities, such as dust particles, contaminate the transmission fluid over time and degrade its quality. i have a 2001 seirra 8.1 with an allison, it runs fine 90% of the time. It only held 12 hg of vacuum, so we believed we found out the culprit. at 75 mph on the highway, if the tranny was stuck in 4th gear, you would be seeing 3000+ rpm. The source of this problem could be obstacles building up in the governor, modulator, or valve body passages. Though, there are still some issues that can be found on them. Upon returning the vehicle to the customer, he requested they call or stop by in about ten days to verify the fix. Reproduction in whole or in part without permission is prohibited. Carlisle Radial Trail HD vs Goodyear Endurance: Which One? If your Silverado is shifting hard, and you get the check engine light, there may be a diagnostic trouble code stored in the memory. Bad Shifter Cable Apart from this problem, low transmission fluid can also lead to transmission overheating. When your car vacuum line is clotted, disconnected, or twisted; this could cause extra pressure to vehicle transmission which makes the gear hard to shift. It is responsible for holding the C2 (Overdrive) clutches and synchronizes in speed to the input shaft on the 3-4 upshift. He has been working as a car mechanic for over 10 years, and the majority of them specialized in advanced car diagnostics and troubleshooting. the way the Allison shifts with increasing speed (when in normal mode, not tow/haul), is to go 1st gear, 2nd gear, 3rd gear, 4th gear, 5th gear, then like 5 mph/couple seconds later after the 4-5 shift, the converter locks up and stays locked all the time in 5th gear until your speed drops below 45mph. 6 Signs Of Low Transmission Fluid And How To Check the Level, 5 Symptoms Of A Bad Transmission Cooler and Replacement Cost, 6 Symptoms Of A Bad Transmission Control Module (TCM), 5 Symptoms Of A Bad Transmission Mount and Replacement Cost, Transmission Fluid Leak When Parked - Causes And Fixes, Car Wont Accelerate But RPMs Go Up: Causes & Fixes. With proper maintenance and normal usage. While there are problems that come with this transmission, one can say that those problems are overshadowed by the extremely good performance owners get out of it. So, If you do not know which fluid is suitable for your transmission system, consider going through the operator manual. This is a very stressful shift for this specific component and can cause it to fail. GM just uses the Allison name to get people to like the new transmission and have them think it was made by this top company. Our Billet C2 hubs also have an oversized fat shaft to ensure the complete and total obsolescence of this problem. Introduction to the Allison 1000 Transmission: When we build our coveted and durable Allison transmissions and rebuild kits, each one is designed to never return broken. Much like old hemi and Ford motors, the outer gear can get compressed to one side opposite the side where pressure vents, causing disproportionate centrifugal to wear. We won't send you spam. believe the overheating is an internal issue. One of the things it has not been able to do is remove all the problems associated with those devices. A mechanic will examine it thoroughly and identify the cause. I have a 2016 Chevy 3500 that will not go into D. It started acting up a little about 6 months ago. Weak batteries could cause it or they could just be hicups in the programming. It is highly unlikely that a valve body will cause a clunk on a down shift Harsh upshifts and down shifts are tie ups. It is for this that many Allison 1000 Transmission owners report that it will often shift just fine up until its final moments. So you are suggesting like every third or fourth oil change, swap out the fuel filter? The Allison 1000 is a densely electronic transmission, relying on many solenoids to open and close at the appropriate times for it to operate. So, check the level and make sure that the fluid is healthy. The friction lining on the Allison clutches is rather thin, so when a clutch drags frequently or a tremendous amount of load is disproportionately obligated to one clutch pack, it will likely isolate itself as most problematic. These are important factors to consider when upgrading the biggest failure point in the OEM Allison 1000 Transmission. Besides, everybody has there own way to describe the same problem. Allison is not with GM anymore and hasnt been for about 15 years. New Member. This means that there are 2 overdriven and 2 underdriven gears. Replaced TCM and checked wiring back to trans still nothing. The vehicle has experienced torque converter shudder since the purchase date of 06/28/2016. The 10-speed Allison is no exception. If you have transmission control system malfunction codes, including solenoid valve problems: P0700: Transmission Control System Malfunction P0751: 1-2 Shift Solenoid Valve Performance P0753: 1-2 Shift Solenoid Valve Electrical P0756: 2-3 Shift Solenoid Valve Performance P0758: 2-3 Shift Solenoid Valve Electrical