Th400 overdrive

Jeep, Ford small-block and Buick V-6 adapters are available to convert your 4WD to the TH400. Used TH400s are available for between $200 and $500, depending on their mileage. Many companies offer rebuilts, which sell in the $600 to $900 range, but cores are usually required. Neutral switches sell new for around $50.

Th400 overdrive. This is a very rare 12,000lb GVW overdrive unit for a short tailshaft TH400 manufactured by Doug Nash Engineering. This one is in good condition.

Plug the vacuum hole in the carburetor or the port in the EFI with a cap. Install the TV cable. (Black unit directly below the throttle cable). Note: Powerglide, TH350 and TH400 transmissions use a vacuum controller to up-shift the gears. Push the end of the TV cable through the hole in the mounting bracket.

This Monster Powertrain Package is complete with all the features you need for a reliable Chevy 383 & Automatic Overdrive TH400 Transmission from a researched and developed combination of components. INCLUDED FREE - No Fault Warranty A 1-time no questions asked repair or replacement. Covers Shipping, Freight claims, Installation errors ...700R4. The 700R4 is an improved and upgraded model compared to its predecessors-TH350 and TH400. The GM THM700R4 is a 4-speed automatic-shift overdrive transmission installed longitudinally (front to back) over vehicle chasses. The 700R4’s performance is comparable to the GM 200-4R but sports a lengthier transmission.Clearly, the biggest difference between the TH400 vs 4L80E is the 4L80E’s overdrive gear. Although they come from different eras, there is quite a bit that these two transmissions have in common. The mere fact that people are so interested in this topic is a testament to the absolute bulletproof reputation of the TH400. There aren’t too ...Regarding trying 3.08's before an overdrive, consider how much time will be spent at highway speeds. I have 3.07's behind a low-rpm, torquey 454 and TH400. Traffic has gotten so bad in the last few years that I drive on the highway only about 50% of the time, which is the only time lowering rpm's is relevant.Find ATI TH400 Transmissions and get Free Shipping on Orders Over $109 at Summit Racing! ATI Performance Products TH400 transmissions offer great performance for 400 c.i.d. or larger big blocks. Modifications and options include: * Fully blueprinted and equipped with high-flow lube circuits, increased torque capacity, and …A 200-4R would be a better candidate to replace short shaft Th400. Possibly the same driveshaft, different yoke, same crossmember. Even installing a 700, you should be able to use the stock crossmember in a Chevelle, except a convertible. ... If i were to go with the 200 overdrive tranny, would i need the same stall converter i have now on the ...This is a very rare 12,000lb GVW overdrive unit for a short tailshaft TH400 manufactured by Doug Nash Engineering. This one is in good condition.I just had a Level 2 - 200r4 from Bow Tie overdives installed. The big difference between the 700 and 200 is the first gear ratio. The 700 is 3.06 and the 200 is something like 2.7. This means a lot less of a torque drop unless your engine is built for it. I'm still evaluating the difference from the TH400 to the 200.

TH400 (CX) with Coan 8" converter, GV-OD, 8 track still on console and best et 10.495, 128.79mph 1.428 60' All with 1960's stuff. (except tires and converter) ... its preset with certain MPH that it will turn the overdrive unit on, and also its made to protect the overdrive unit to be on while in reverse or under 20MPH thats (which will damage ...The T5 offers overdrive for light-duty early Jeep applications that have the Dana 18 or Dana 20 transfer cases. AX5. As found in Jeeps behind the 2.5L, the AX5 can be adapted to the Jeep Dana 300. ... I-III vehicles, the 4L80E is the takes everything awesome about the TH400, and adds overdrive and a lock-up converter to it.Find Parts and Accessories th400 overdrive KEYWORD and get Free Shipping on Orders Over $109 at Summit Racing! $20 Off $250 / $40 Off $500 / $80 Off $1,000 - Use Promo Code: CARCARE Vehicle/Engine Search Vehicle/Engine Search Make/Model SearchFeb 2, 2018 · Here you can see the straight-cut pinions from Coan installed into the output carrier. In a Turbo 400, the stock first gear checks in at 2.48, with 1.48 as the second cog, but with the power of our supercharged small-block in Evil 8.5 paired with the tiny 235 drag radials running on radial-type prep, a custom 2.73/1.56 gearing was deemed optimal. Apr 10, 2014 · 343 posts · Joined 2009. #1 · Apr 10, 2014. Can anyone tell me about Doug Nash overdrives for TH400. I have found one thats reasonably priced and am looking at buying it for my 88 3500 dualie tow vehicle. It's 496 BBC. I want to drop highway RPM & hopefully improve the fuel economy. My trailer is about 4 ton, loaded. GM retroactively called the TH400 the "3L80" when the 4L80E debuted. The 4L80E (and its 4L85E derivative) are candidates for heavy, powerful vehicles in need of an overdrive transmission.

That's the overdrive version of the TH400 but it is little different in size. Really good transmission though and better gears for the street than the 700R4/4L60(E) is. The 4L60 basically is a renamed 700R4 and the 4L60E is the electronic version of it. Both the 4L60E and the 4L80E will need a controller which adds an expense.You can think of this trans as basically a TH400 with a 25 percent overdrive tacked on. The 4L80E transmission was mostly used in 34- and 1-ton trucks and larger SUV applications beginning in 1991.That's why I'm interested in the GV TH400 overdrive. Solves the high RPM on the highway problem and improves racing performance over just running the TH400 alone. All that and the TH400's renowned durability is retained. A 700R4 feels like a step in the wrong direction, especially when I already have a good TH400 in place.Automatic 4-Speed BW 4401 2 1/2″ Tailhousing 4L80E w/fixed yoke, Gas Engine.Replaces 2 1/2″ tailhousing, requires GM speed buffer (incl).99-02 4×4 1 ton dually extended and crew cab trucks, check tail length and yoke to confirm & provide axle ratio and tire size. Price : $3,795.00.

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Turbo-Hydramatic or Turbo Hydra-Matic is the registered tradename for a family of automatic transmissions developed and produced by General Motors. These transmissions mate a three-element turbine torque converter to a Simpson planetary geartrain, providing three forward speeds plus reverse. The Turbo-Hydramatic or Turbo Hydra-Matic (THM ...May 28, 2018 ... Cowmaro Apparel: http://jdads.bigcartel.com/product/cowmaro-tee ...Swapping out an early automatic for a more modern one is a bit more difficult as the venerable TH-series (350 and 400) and their overdrive brethren won't just bolt up to early B-P-O (Buick, Olds ...Clearly, the biggest difference between the TH400 vs 4L80E is the 4L80E’s overdrive gear. Although they come from different eras, there is quite a bit that these two transmissions have in common. The mere fact that people are so interested in this topic is a testament to the absolute bulletproof reputation of the TH400. There aren’t too ...Today, HTC has revealed their latest consumer-focused headset, the $499 Vive Flow. It’s designed for portability with a compact design and 189 gram weight, though there are some bi...

According to Gear Star’s Zack Farah, each comes with a 24-month/24,000-mile warranty to back it up. Replacing the old TH400 with Gear Star’s Level 3 4L60 in a ’72 Chevy C-10 was basic, but care needs to be taken while adjusting the TV cable to ensure the right change in line pressure inside the tranny to coincide with how much your foot ...A 2wd 4L80 will bolt right in place of a TH400. It is 1" longer than a TH400 but has the exact same output shaft and mount so you wont need to change anything else. You can get a core for $200 and have it rebuilt at a local shop for less than $800 usually. Its only about $150-400 for a complete rebuild depending on how much you want to ... The Truck was rented for the 2004 Quatar Rally and won that event also. Chevrolet Pro Truck – 850hp with a Th400 and Gear Vendors Under/Overdriveâ„¢ used in all the championships. [email protected]. GEAR VENDORS, INC. 1717 North Magnolia Avenue, El Cajon, CA 92020. Toll Free 800-999-9555 • Telephone (619) 562-0060 • Fax (619) 562-1186. Being an entrepreneur is a full-time job. There are no days off, and it's a lot of hard work. Here are my 7 MUST-KNOW tips for every entrepreneur. Being an entrepreneur is a full-t... Essentially a TH400 with overdrive and more rugged internals, the GM 4L85E is the ultimate automatic. When built right, they can handle over 1,000 hp reliably, and best of all, transplanting one into a fourth-gen is much easier than Internet mythology suggests. Sep 6, 2016 · Gear Vendors is an aftermarket, bolt on overdrive for the TH400 (and many others). Not the least expensive route but seems to be very dependable and strong. You should have plenty of room for this without any cutting also. Gear Vendors under/overdrive auxiliary transmissions Hot Rods, GM 3-Speed Automatic Performance Car/Street Rod. Here you can see the straight-cut pinions from Coan installed into the output carrier. In a Turbo 400, the stock first gear checks in at 2.48, with 1.48 as the second cog, but with the power of our supercharged small-block in Evil 8.5 paired with the tiny 235 drag radials running on radial-type prep, a custom 2.73/1.56 gearing was deemed optimal.Using antibiotics incorrectly can cause some bacteria to change or permit resistant bacteria to grow. These changes make bacteria stronger, so most or all antibiotic medicines no l...This is also why all GM Callaway Twin Turbo Corvettes with …Although the Gear Vendor's overdrive unit is bombproof, the 4L80E's .75:1 O.D. is better than the GV's .78:1 ratio. And you would be giving up on the locked torque converter. Locking the converter feels like 5th gear and reduces the fluid temp greatly. In O.D. the final drive is 3.08:1.So everybody knows what I am working on my car is a 69 camaro with a 502 BB, Th400 with reverse manual valve body and 4:10 gear in the rear. ... So the overdrive stays engaged through all gears unless you push the button and disengage it. Once you slow down to 20 MPH it shuts off, to ensure you do not go in reverse with it engaged. …[email protected]. GEAR VENDORS, INC. 1717 North Magnolia Avenue, El Cajon, CA 92020 Toll Free 800-999-9555 • Telephone (619) 562-0060 • Fax (619) 562-1186

Gearvendors was a dealer and bought out Laycock when they went belly up. Gearvendors did some minor internal changes including increasing hydraulic pressure to te o/d ring from 500 psi to 900psi. They are generally a . 68 to .70 reduction overdrive. They work best with rear ratio in the high 3s to mid 4s.

TH400 Transmission, Rebuilt TH400 Transmission, TH400, Monster Transmission offers free shipping on TH400 transmissions, also offering completely rebuilt TH400 transmission and turbo 400 transmissions, TH400 rebuild ; 0; 800-708-0087 ... Overdrive Conversion Packages; Black Beast Diesel Transmissions; In Stock Ready To Ship Transmissions; …Mar 12, 2011 · They are pricey new, but they're tough and can be installed behind many different transmissions. 71 SS 454 TH400 2.74 1st gear GV Overdrive 3.55 Gear SC&C Stage 11 QA1's 4 Wheel Baer Brakes AGR Box Straub SR .630 .612 lift 240 256 [email protected]. 83 K20 454 TH475 NP 205 Dana 60 Track Lok Detroit Locker Rear. I just had a Level 2 - 200r4 from Bow Tie overdives installed. The big difference between the 700 and 200 is the first gear ratio. The 700 is 3.06 and the 200 is something like 2.7. This means a lot less of a torque drop unless your engine is built for it. I'm still evaluating the difference from the TH400 to the 200.What transmissions can use an overdrive? GearVendors Overdrives are available in bolt-on units for all the most commonly used classic car transmissions and more, with the most popular models being the GM TH400 Overdrive, Ford C4 Overdrive, Ford C6 Overdrive and GM TH350 Overdrive.Aug 8, 2020 ... Gear Vendors Under/Overdrive transmission parts Review. Gearvendors is bar none the coolest towing & Torque splitting parts to make your rig ...That's why I'm interested in the GV TH400 overdrive. Solves the high RPM on the highway problem and improves racing performance over just running the TH400 alone. All that and the TH400's renowned durability is retained. A 700R4 feels like a step in the wrong direction, especially when I already have a good TH400 in place.The overdrive unit will work on the back of a Saginaw 4-speed as well. They really aren't any stronger. "Thunder is good, thunder is impressive, but it is the lightning that does the work." ... Gear it low in the rear, run a TH400, can still cruise highway speeds and get 20mpg off the gas, then lay into it and let the good times roll :beers:I don't have the tail piece for the TH400 and dont want to deal with making that functional again without the overdrive. Also, we would be interested in trading for a BBC supercharger, preferably a procharger. Thanks Paul 1969 RS Camaro 1985 Buick GN 2005 F-250. 02-17-2011 #7.Description. Automatic 3-Speed TH 400 4″ Tailhousing. Replaces 4″ tailhousing. Small block and Big block cars. Additional information. Product ID. 11184. Weight. 0.06 kg.Camaro Overdrive Conversion Kits. 1967-2021 Camaro Overdrive Conversion Kits Parts. Close. have any question? (866) 358-2277 | Live Chat. ... TH400 Automatic Shifter with Thomson Performance Detent. Part #: SW1001-R | Manufacturer Part #: SW1001-R $577.99 $529.99 (Kit) Add To Cart.

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This is also why all GM Callaway Twin Turbo Corvettes with …That's why I'm interested in the GV TH400 overdrive. Solves the high RPM on the highway problem and improves racing performance over just running the TH400 alone. All that and the TH400's renowned durability is retained. A 700R4 feels like a step in the wrong direction, especially when I already have a good TH400 in place.Apr 24, 2015 · The 4L80E is just a longer, heavier, overdrive version of the TH-400. It uses the same first three gear ratios but adds a 0.75:1 overdrive. This means that with a 3.55:1 rear gear, the overdrive drops the effective rear gear ratio to 2.66:1. This makes the first question more about torque converter selection. The AGPS gene provides instructions for making an enzyme known as alkylglycerone phosphate synthase. Learn about this gene and related health conditions. The AGPS gene provides ins...Are you an avid reader who loves the convenience of accessing books online? Look no further than NYPL Overdrive, a digital reading platform offered by the New York Public Library (...Gear Vendors review. As of 9/21/2012 I completed the install of the under/overdrive gear vendors unit. Once I received the box and looking at the unit it's pretty sweet looking piece and I was excited to get it installed. Now just so everybody knows I'm not a mechanic just a weekend warrior that's learning as I go.May 28, 2018 ... Cowmaro Apparel: http://jdads.bigcartel.com/product/cowmaro-tee ...The 4L80E is a much larger trans­mission with stronger internal com­ponents. The 4L80E was thought to be the modern, overdrive version of the TH400 when it first hit the streets. From a strength and performance perspective, the 4L80E is definitely a player. Its downsides are size and weight.In today’s digital age, reading has taken on a whole new form. With the advent of smartphones, tablets, and e-readers, more and more people are turning to eBooks and audiobooks for...We'll use our 4.10 rear-axle ratio and the 2.48 first-gear ratio of the popular GM TH400 automatic ... The overdrive can also be used to split gears on wide-ratio split transmissions. The torque ...Gearvendors was a dealer and bought out Laycock when they went belly up. Gearvendors did some minor internal changes including increasing hydraulic pressure to te o/d ring from 500 psi to 900psi. They are generally a . 68 to .70 reduction overdrive. They work best with rear ratio in the high 3s to mid 4s. ….

Re: Gearventor overdrive Munro - try going to their website and clicking on 'Contact Us.' You can submit info directly via the site. The email address is the one you have in your post. I have had GV with my TH400 for 10 years and love it. Don't expect a lot of overdrive (.78) but more of a keeping the engine in the power band as they advertise.Looking to improve highway mileage on late model trucks, beginning in 1991 GM upgraded the original TH400 by adding a 0.70:1 overdrive along with complete electronic control to create the 4L80E. This trans is significantly larger and heavier than its three-speed predecessor, but like the 4L60E it is easily employed for performance use in ...Turbo 400 4x4 on sale with Free Shipping, Now offering TH400 4WD, TH-400, Monster 400 Transmission, heavy duty Th400 and heavy duty Turbo 400 with new lower prices 0 800-708-0087Description. Automatic 3-Speed TH 400 4″ Tailhousing. Replaces 4″ tailhousing. Small block and Big block cars. Additional information. Product ID. 11184. Weight. 0.06 kg.Aug 23, 2006 · Mechanical Overdrive on TH400. I have a mechanical overdrive that replaces the tail shaft on a TH400 transmission. I have tried everything to find out what it is and who made it. My BB Chevy is pushing 700HP and the overdrive holds up. The only markings on it are R11-1P, W.G. Div. and J-26-62 which would suggest it was built January 26, of 62. GM 4-Speed Auto - Gearvendors. GM 4-Speed Automatics 700R4/4L60E/4L80E There are two basic GM 4-Speed automatics: The light duty 700R4/4L60E found mainly in half ton and car applications, and the heavy duty 4L80E in the heavier applications. 700R4/4L60E’s have a low 3.06 first gear which is good for initial take off but this...But the TH350 and TH400 three-speed versions (and their two-speed Powerglide cousin) fall short when it comes to highway cruising. The reason for this is … Th400 overdrive, The Truck was rented for the 2004 Quatar Rally and won that event also. Chevrolet Pro Truck – 850hp with a Th400 and Gear Vendors Under/Overdriveâ„¢ used in all the championships. [email protected]. GEAR VENDORS, INC. 1717 North Magnolia Avenue, El Cajon, CA 92020. Toll Free 800-999-9555 • Telephone (619) 562-0060 • Fax (619) 562-1186., The big difference between the 700 and 200 is the first gear ratio. The 700 is 3.06 and the 200 is something like 2.7. This means a lot less of a torque drop unless your engine is built for it. I'm still evaluating the difference from the TH400 to the 200. I'm not convinced it was a good decision., This Monster Powertrain Package is complete with all the features you need for a reliable Chevy 383 & Automatic Overdrive TH400 Transmission from a researched and developed combination of components. INCLUDED FREE - No Fault Warranty A 1-time no questions asked repair or replacement. Covers Shipping, Freight claims, Installation errors ..., In today’s digital age, libraries have evolved to offer more than just physical books. The New York Public Library (NYPL) is one such example, with its innovative digital platform ..., The Powerglide (2-speed) shifter was able to be used without modification for the TH350 or TH400 (3-speeds). However, when switching to a 4-speed overdrive automatic this is no longer true. The conversion was not designed for, and does not include any provision for, use of the "Rally" shifting option., Learn about upgrading to the TH400 transmission and how it can improve performance and reliability on your 1963 Oldsmobile with our Classic Car Member Q&A. ... although I would suggest going one step further and adding overdrive with the use of a 700r4 or 4L60 transmission. The original Slim Jim transmission is a relatively narrow …, Upgrading TH400 to 4speed with overdrive - Gear Vendors? 1967 gto gear vendors upgrading to 4 speed automatic. Jump to Latest Follow. 19K views 23 replies 6 …, Have a TH400 w/ GV overdrive and all it superior benefits, BUT have to cut up my nice car.-or-Settle for a beefed up 700R4 for about the same cost and have a less sturdy transmission and none of the racing performance advantages of the GV gear splitting, but my nice car does not get cut up. I wish GV would just engineer the unit to fit …, Parts Classifieds - Gear Vendors Overdrive for th400. Add overdrive to you 3-speed! - Technically a laycock unit (gearvendors before they had the name- same internal parts and assembly) this is for a short tail turbo 400. Since these pics it has been bead blasted clean and is ready to be bolted on! Has a new..., Reprint from Hot Rodding Magazine, September 2008. The gear Vendors overdrive kit for the Turbo 400 had everything we needed to add a pleasant 0.78 overdrive to our big-block ’68 Chevelle. The kit costs $2,595 (PN 3D0400AFS), and includes everything except labor and a shortened driveshaft. At $4.27 per gallon for 91 octane premium unleaded ..., Cons: it’s really heavy (110 pounds MORE than a TH400) and has the highest HP loss of all transmissions, can easily be built for 1,000 HP. 5-6 grand built “right”. -Gear Vendors overdrive. Cons: Gotta beat the floor up a bit, I think it’s 60 to 80 pounds, bad drive line angles. Around $2,700.00., The TH400 is an automatic shift, three-speed, longitudinally positioned transmission. It is widely regarded to be a supremely durable and legendary transmission. The TH400 is conservatively rated at 450 ft. lbs. of input torque. Aftermarket building techniques take it well past that figure., Oct 21, 2022 · GVW or Gross Vehicle Weight. This name change was necessary as it made readily identifying the transmissions easier. This was also the year an early introduction of the 4L80-E transmission, the successor of the Turbo 400 Transmission that has overdrive, was made. The TH400 transmission is an electronically-controlled, heavy-duty version of a ... , Jan 29, 2018 · Clearly, the biggest difference between the TH400 vs 4L80E is the 4L80E’s overdrive gear. Although they come from different eras, there is quite a bit that these two transmissions have in common. The mere fact that people are so interested in this topic is a testament to the absolute bulletproof reputation of the TH400. There aren’t too ... , The name also changed from TH400 to 3L80 in 1990. The name 3L80 comes from 3-speeds, longtiudinally positioned, and 8,000lbs Gross Vehicle Weight. The name change was to help identify the transmissions better. The early 1990’s is also when we see the introduction of the 4L80-E, which is the successor of the TH400 that has overdrive. , According to Gear Star’s Zack Farah, each comes with a 24-month/24,000-mile warranty to back it up. Replacing the old TH400 with Gear Star’s Level 3 4L60 in a ’72 Chevy C-10 was basic, but care needs to be taken while adjusting the TV cable to ensure the right change in line pressure inside the tranny to coincide with how much your foot ..., Sep 27, 2018 · GEAR VENDORS provides an overdrive product to race cars and trucks up to 2,000 hp. This product is particularly well suited to the special demands of Drag We... , But the TH350 and TH400 three-speed versions (and their two-speed Powerglide cousin) fall short when it comes to highway cruising. The reason for this is …, Feb 11, 2022 ... 13:55 · Go to channel · Gear Vendors Activation in 1970 El Camino with turbo 400 transmission. Scott Cerreta•21K views · 2:38 · Go to c..., C3 General - C3 transmission swap for overdrive. Advice from a mechanic. - Hey ya'll. ... I'm going to swap out my TH400 for either a beefed up auto overdrive or a TKO600. I'm still researching, but don't want to run 3000 rpm once I've rebuilt my drive train. Good luck! Reply Like 10-19-2016, 05:34 AM ..., This ratio is ideal for getting the best speed. If you want to get your car moving fast, get the TH400. And according to Gear Star, 4L80E transmissions have nearly 25% overdrive and are 4 inches longer than the TH400. On the other hand, a higher overdrive gear ratio facilitates faster acceleration. The 4L80E has such a ratio, which is …, Photos show locals trying to dig out and make sense of the work to be done to rebuild after such an unforgiving storm. Hurricane Michael made landfall on Florida’s panhandle just s..., The TH400 is an aluminum cased three speed automatic transmission that was produced by GM. It was introduced for the 1965 model year and made its debut in Cadillacs, and is respected for its durability and adaptability. The TH400 came in two wheel drive and four wheel drive vehicles, passenger cars and heavy duty trucks, as well as GM vehicles ..., As it depends on the make, model, and year of the transmission. However, a general rule of thumb is that the torque converter ratio (TCR) for a TH350 transmission should be around 3.0. The TH400 transmission turbo is a 4-speed automatic transmission. It has a Ratios of: 1st Gear: 3.42 2nd Gear: 2.92 3rd Gear: 2.48 4th Gear: 1., Aug 2, 2004 · I just had a Level 2 - 200r4 from Bow Tie overdives installed. The big difference between the 700 and 200 is the first gear ratio. The 700 is 3.06 and the 200 is something like 2.7. This means a lot less of a torque drop unless your engine is built for it. I'm still evaluating the difference from the TH400 to the 200. , This is a look at the interior and the PCS electronic shifter console, paddle shifters and gear vendors buttons. I take a drive and describe how these compon..., General Motors wanted a powerful automatic overdrive, hence, the introduction of the 4L80e. As stated above, the 4L80e used most parts of the TH400 but added overdrive gear, lockup converter, and electronic controls. The addition of overdrive led to the increment of the 4L80e transmission case—about 1½ inches longer than the TH400., The TH400 ( Figure 1) has four endplay tolerances (NOT to be confused with clutch clearances) that should be examined and corrected during repair. However, GM’s published rebuild procedure only references two of them! With two endplay tolerances being ignored, you can imagine why these meltdowns are occurring. Figure 1., Jan 3, 2018 · i like the thought of keeping my th400 but have overdrive. at $3100 it wont be happening till later this year if at all. nothing needs modifying except rear drive line length. is there a way to justify this over 4l80 swap? it'd be nice to hear from the knowledge base here on the matter, maybe i can start scouring CL for a rebuilt/rebuildable ... , Watch the tips and tricks as we install a Gear Vendors Over Drive in Brads 1971 Camaro., Parts Classifieds - Gear Vendors Overdrive for th400. Add overdrive to you 3-speed! - Technically a laycock unit (gearvendors before they had the name- same internal parts and assembly) this is for a short tail turbo 400. Since these pics it has been bead blasted clean and is ready to be bolted on! Has a new..., Essentially a TH400 with overdrive and more rugged internals, the GM 4L85E is the ultimate automatic. When built right, they can handle over 1,000 hp reliably, and best of all, transplanting one into a fourth-gen is much easier than Internet mythology suggests. ,