For more information about what data PayPal services collect and how that data may be used, visit the "Legal Agreements for PayPal Services" page to review the PayPal Privacy Statement and Statement on Cookies and Tracking Technologies that apply in your location (the Statement on Cookies and Tracking Technologies that applies to each region is linked from within the applicable PayPal Privacy Statement). This means that at a 2:1 torque multiplication ratio, an engine that is making 300 lb-ft of torque at a stall speed of 2,500 rpm will actually apply 600 lb-ft of torque to the input shaft of the transmission as the car leaves the starting line. The turbine has a spline that attaches to the transmission input shaft, which connects to the internal parts of the transmission to shift gears and provide power to the wheels. The drive fan moves air across the blades of the driven fan (which is turned off). i take it your a writer and not a trans guy ,but maybe someone could answer the question. So when the torque converter clutch engages there should be almost 0rpm difference between tc slip desired and tc slip act. and our You only monitor it when the converter is locked. The wire chaffing is a definite possibility. Once the vehicle is moving at a constant speed, the speed difference between the impeller and turbine diminishes, eventually reaching a minimum point known as coupling stage. Keep reading to find out these common torque converter problems and how to fix them. One of the fundamental differences between a fluid clutch (a fluid coupling or torque converter) and a mechanical plate clutch is slippage. Terms of Service - I drove only sticks for years by choice. I had unlimited tow loaded and he thought maybe it wasn't playing nice with my trans. There was also a kickdown mechanism that allowed the driver to disengage the clutch at road speeds between 13 and 56 mph (21 and 90 km/h) by flooring the accelerator, allowing the torque converter to again multiply torque. The _gat cookie, which may appear as _gat_gtag_UA_6113964_2, was sometimes set along with the _ga and _gid cookies to control how frequently requests were sent to the Google Analytics servers; this cookie typically persisted for only a few minutes at a time. Third, make sure that your engine is running right because a transmission chuggle can be caused by many things. Studebaker-Packard (the two companies merged in 1954) dropped both of these transmissions after the 1956 model year. This is why lifting off the throttle in a car with a fluid coupling or torque converter can feel almost like shifting into neutral. i called a trans shop and he had no answer,but it sounded strage to him. For people who want a broader overview, I would recommend a book by Philip G. Gott entitled Changing Gears: The Development of the Automotive Transmission, published by the SAE as part of their Historical Series in 1991. Whether it will add to my working knowledge is debatable, but my brain will benefit from the workout. For comparison, a four-speed Wilson pre-selector has four planetary gearsets, four sets of brake bands, and a cone clutch, which is a lot of pieces. If you correctly enter the password, the site saves this cookie on your device to allow you access to the password-protected post or page. Dr. Tranny helped for a short time and then the car became entirely undriveable. abs, do you have any recommendations on how to troubleshoot a failing torque converter using ForScan? This is how the first fluid couplings were designed, but they were hideously inefficient because of high slippage. The replacement was a cheaper and somewhat simpler Borg-Warner unit which Studebaker-Packard called Flightomatic that deleted the DGs lockup clutch. As you can see I was experiencing multiple issues, all of which were exacerbating the clutch slippage and/or shuddering issue. if you dont hammer on it everyday it will last you a long time.. my stock converter had 350 rpms of slip on the 310 tune and the truck still had all kinds of power even locked. When I replaced my transmission and converter, I replaced two mounts and the two dog bones under the engine. Transmission Range) start a datalog or have an assistant drive and watch Torque Converter Slip Actual (TCA) and Torque Converter Slip Desired (TCD). I cant imagine the hours of work which you must have put into understanding these various transmissions, to say nothing of writing up a description that a simpleton like me could (mostly) understand. The wahFontColor and wahBgColor cookies, which are set if you alter the site's color scheme, normally expire after about 14 days, but you can remove them immediately by clicking the "Restore Defaults" button on the sidebar. ), These cookies were previously used by the Google Analytics service to collect information about visitors and their use of the Ate Up With Motor website. Torque converter slip question I was monitoring some Torque converter params for my 4R55E with my in dash scantool. Required fields are marked *. I was running the KEM 250 and 310 tunes. Failing Torque Converter Clutch with Slippage - Ford Flex If you shop at Amazon.com (for anything), use this link to support FordFlex.net! In the diagram above, the yellow arrow again illustrates the flow of power, this time in third (top) gear. Your Transmission Gear Ratio at Finish Line. Diagnosing a potential Torque Converter problem with a Scan tool. This is a red flag that lets you know you may need an expert to repair it for you. Thu Aug 29, 2019 1:33 am, Post Gears Magazine - Nag 1/722.6 P0741 TCC Slip Tire slip is likely causing your speed difference. These torque converters allow some slippage but it should not vary much from the desired PCM value. It ran pretty good. If you change certain aspects of the site's appearance using the accessibility sidebar, it may set these cookies to manage and remember your settings. How much torque converter slip is OK? | Chevy Nova Forum Failing Torque Converter Clutch with Slippage - Could be your TCC Solenoid, Re: Failing Torque Converter Clutch with Slippage - Could be your TCC Solenoid, https://www.ecoboostperformanceforum.co 733.0.html. The first automatic transmissions employed what was called a fluid coupling to connect the crankshaft with the transmission. Some iterations of the Studebaker Automatic Drive/Borg-Warner DG started in first gear, but early transmissions started in second unless the driver manually selected Low. Well Aaron . One or more wp-saving-post cookies may be set while creating and/or editing posts or pages, to help manage version control and the autosave feature; these cookies normally expire after about 24 hours. How exactly are you measuring how much the tc is slipping? Once your torque converter starts failing, you need to be knowledgeable about what torque converter problems will disable your car? Your first course of action, if you notice yourtransmission or torque converter has started to slip or shudder is checking your fluid level. Fluid clutches fluid couplings and torque converters have many advantages for automotive transmissions, but with those benefits comes a cost: fuel-wasting hydraulic slippage even at cruising speed. Twice last week, when I came up to a stop light, the engine bogged down to 400rpm then recovered back to normal idle. These early units operated on the same principal of using one electric fan to drive another. by SirHandyMan Fri Mar 29, 2019 6:54 pm, Post Cookies whose names begin with "_ceg" are associated with the Crazy Egg web analytics service (which is subject to the Crazy Egg Privacy Policy and Cookie Policy). (author diagram). In first and second gears, the converter turbine drove the front annulus (ring gear). (These cookies may not be set at all for administrative users unless they access the publicly visible portions of the website and/or update their consent settings e.g., by accepting an updated version of the Privacy Policy. This viscous connection is transmission fluid. The combination of a smaller-diameter and lighter converter means that less engine torque is required for acceleration. & Tm. It's also important not to undersell converter weight as a contributing factor to maximizing acceleration. Akamai is a registered trademark or service mark of Akamai Technologies, Inc. in the United States (Reg. A torque converter clutch (TCC) is an important element of automatic transmissions because it affects fuel economy and driveability. This is most noticeable from about 1200-1800 rpm. Filling the cylinder with pressurized oil would lock the pressure plate to the clutch plate itself, forcing the clutch and input shaft to rotate with the torus cover at engine speed. It was followed in fairly short order by the 1950 Studebaker Automatic Drive, which took a somewhat different approach to the same problem. The DG series transmissions were notionally three-speed automatics (although early iterations were designed to start in second gear) with a torque converter lockup clutch. Logging in sets the wordpress_logged_in_xx, wordpress_sec_xx, and/or wordpress_xx cookies, which store the user's login credentials to allow access to the administrative dashboard and other administrative functions; there may be multiple iterations of each cookie. New to the site and found it because of this read. The torque converter is made up of five parts: The stator is called the middleman. Hence, you've commanded your torque converter every time your car shifted gears. The effective dates of the current versions are: Paid advertisements and/or sponsored links on Ate Up With Motor will be identified with words such as "Sponsor," "Sponsors," "Sponsored Link(s)," "Sponsored Content," "Ad," "Advertisement," "Advertisement(s)," or "Paid Promotion" (and/or by images or icons containing such words). At some point Ford modified the wiring to include a thick rubber insulator on the wires that extended beyond the edge of the intake manifold to prevent the chaffing. In this diagram, the yellow arrows show the power flow in second gear. by SirHandyMan Fri Mar 29, 2019 3:24 pm, Post When starting, the fluid clutchs driving torus (the impeller) may reach a speed of 2,000 rpm or more before the driven torus (the turbine) begins to move at all, a point known as stall. If the engine isnt free to turn faster than the driveshaft at rest or extremely low speeds, the engine will stall! How To Log Transmission And Torque Converter Slip In HPtuners!!! (For this cookie, "xx" will be a cryptographic hash.) by SirHandyMan Fri Mar 29, 2019 8:27 pm, Post We were wrong. Although this arrangement sacrificed some of the smoothness that was the main rationale for early automotive torque converter transmissions, it made Ultramatic more efficient than the early Dynaflow, at least at cruising speeds. Im not able to provide repair or maintenance advice, sorry! Therefore, a lockup clutch needs to be accompanied by some mechanism to selectively engage or disengage the clutch. But now with the Spartan 275 I am seeing 18.24 at WOT with the converter locked. Currently the vehicle is much better to drive. I re-used the "new" valve body and decided to try out my original solenoid pack to avoid having to reprogram the PCM with the new calibration for the solenoid pack that came with the recycled transmission. When it comes to automatic-equipped street machines and drag-race cars, the torque converter is a welded-up magic box that few enthusiasts know much about. When coasting, the turbine overruns the impeller, which causes slippage, but relatively little braking effect. What to Do to Fix Your Contaminated Transmission Fluid. (Google, DoubleClick, YouTube, and other related marks and logos are trademarks of Google LLC. Your car will vibrate even when youre not going very fast. These torque converters allow some slippage but it should not vary much from the desired PCM value. It stayed there(18.24) from 60mph to 90 when I let off of it. Some persist for only a few minutes, or until you close your browser (or other user agent); others may remain in your browser (or other user agent) as long as your individual settings permit. I havent studied the Wilson preselectors in any great detail, but if youre curious, the applicable U.S. patents are US1404675 and US1796904. Like the contemporary Buick Dynaflow, Ultramatic was designed to operate most of the time in its direct drive top gear. A flyweight 2,800-pound car like an early Mustang or Chevy II could use less multiplication to successfully launch on their relatively smaller rear tires.