Hokie LX
SILVER Star
Hi all,
I wanted to do a thread detailing my install of my Doug Thorley headers on my 2003 LX470. I haven't seen this much detail anywhere that I could find showing the tools that make this job easier so I hope it will be helpful for someone looking to do this job by themselves. This won't be a how-to per-say but I will share some of the tips and tricks I learned while doing this job as well as some of the tools that I found invaluable! It will also cover some of the things I did wrong that others should keep in mind while doing this job.
I will say that this job was not as daunting as I had originally believed. After all, it's just nuts and bolts, right? (/s)
Amazingly, my stock headers were not cracked but I could have sworn they would be.
What was getting installed...I ordered the DT headers and exhaust from the recent group buy on FB. This will focus on the headers as the exhaust install is very straightforward.
Parts I ordered for the header install. All Toyota OEM parts.
Total cost of parts from McGeorge Toyota - $136.62
Tools I used:
I used a lot of various extensions, ratchets, breaker bars, swivels, etc... But these tools listed are ones that not everyone may have on hand but made this job MUCH easier!
1. Flex ratcheting wrenches. I ordered some GearWrench stubby and normal length ratchets which I used extensively as they were great for accessing and snugging down the new manifold nuts in hard to reach areas. I bought these but any good quality flex ratcheting wrenches should work. I had some cheap HF ones previously and the ratcheting mechanism broke on 2 of them in another job I was doing the week before...buy once, buy quality!
Amazon product ASIN B000HBAI40 <-- Stubby wrenches
Amazon product ASIN B07Y49L5PS <-- normal length wrenches
2. Note on spline sockets...I know most people are recommending these to remove the stubborn factory manifold nuts but I did NOT have good luck with them in my experience and stripped two nuts using them. I used my Kobalt 6-pt sockets and they worked great for me on all of the other nuts! Definitely use good quality 6pt sockets as I was exerting A LOT of torque to remove many of the manifold nuts. Don't use 12pt sockets for obvious reasons.
3. Extraction sockets - I tried using some spline sockets to remove the manifold nuts and it stripped two of them. I had to buy some deep extraction sockets to remove them and these worked a treat! The short extraction sockets I had already were not long though to fully seat on the nut. Longer ones pictured below.
Amazon.com - https://www.amazon.com/dp/B083FSBFQ6?psc=1&ref=ppx_yo2_dt_b_product_details
4. Socket depth... I found that my Kobalt 1/2" 14mm socket was the best option for accessibility and seating fully on the manifold nuts to remove them. It is longer than a 3/8" short socket but still long enough to cover the entire manifold stud and nut fully while still being shorter than a deep 3/8" or 1/2" socket. This shows the length difference between the various sockets I had on hand.
5. Swivel sockets - Honestly, I found that the hardest part of this job for me was reinstalling the dip stick tube retaining nut on the driver side. With the new header in, it leaves very little room to access and install the bolt. I used a swivel socket I had in my toolbox which made this easier after trying for way to long to do it by hand or with a 1/4" short socket. After messing with the other methods for the better part of an hour, I got it in with a 1/4" swivel socket in a under a minute fishing through the fender well around the shock mount. Swivel socket I used is pictured below on the far left.
6. Extensions - I found that I had to use a breaker bar and my jack handle as an extension to break 12/16 of the manifold nuts loose. They were well aged in place after 18 years. If you have a "weathered" truck with some corrosion, be prepared for this. I had to bring the extensions outside of the fender to use my jack handle to get enough leverage which required probably ~24-30" or more of extensions to make this work. Have some on hand!
7. E10 socket to install new manifold studs and re-torque any stock ones that didn't pull out with the nut. I had these on hand from my BMW days but get some if you don't have them already.
Picture of the maybe uncommon tools I used. Not including the standard ratchets, extensions, etc.
Tips/Tricks/Lessons Learned:
1. This may be obvious but soak everything in PB blaster for days ahead of time. My truck has minimal if any rust and I had a 1/2 breaker bar with the top of a jack handle for 12 of the 16 header bolts to crack them loose.
2. Take out the catalytic converter pipes for extra working space and to remove the driver side header easier. It's only 2 more bolts and disconnecting the 02 sensor and it made it much easier and allowed for greater accessibility from below. It also makes removing the factory headers and fishing the new ones into place very easy.
3. I didn't remove the steering linkage or heat shield on the driver side like some of the how to's tell you to. I took the shield out with the header and had no problems. I wasted far too much time trying to remove these two things before starting on the driver side header nuts and ended up not needing to remove them at all to do the job.
4. RELEASE AND REROUTE THE O2 SENSOR WIRING HARNESS ON THE PASSENGER SIDE AFTER YOU REMOVE THE STOCK HEADER AND BEFORE YOU PUT THE NEW HEADER BACK IN. Makes it WAY easier to undo since it's virtually inaccessible with the new header installed. I learned this the hard way...
5. Route the passenger side O2 sensor harness ABOVE the header. I did mine below initially and found that it rubbed the header and would melt due to heat. I rerouted it above and have no issues and plenty of clearance. There may be other ways to do this but I found this to be the best way. I released the 2 harness clips and ran the wiring up towards the top of the engine bay and then back down above the collector to the O2 sensor.
6. I used virtually all of the 3/8" and 1/2" extensions, swivels, adapters, ratchets, breaker bars, etc that I had. To get the jack handle and breaker bar outside of the fender to crack many of the bolts loose, I was using ~24-30" of extensions. Use good quality ones that don't flex or have a lot of slack. You need socket swivels to get the socket to seat flush on the manifold bolt or else you don't stand a chance.
7. For access to a couple of manifold nuts, I combined both of my swivels to fully seat the socket on the nut.
8. I loosened (don't completely remove) the trans mount bolts and passenger engine mount bolts to allow engine to flex up high enough to put in a 2x4. I couldn't get mine high enough to get a 2x4 in there without doing this. Be careful not to crack your rad fan shroud when jacking up the engine. I rotated the top fan fins to 11 and 1 o'clock and it was fine. By not fully removing the passenger side and trans mount bolts, you don't have to worry about the engine seating back down in the correct location and having to fight the engine to drop into place when you put it back down.
9. The flex ratcheting wrenches are a life saver. They made this job a lot easier.
10. I removed the air box for easier access to some of the front top manifold bolts on the passenger side. I got a few of the top bolts through the top of the engine bay as it was easier. Removing the air box allows for more space to cycle the ratchet/breaker bar.
11. Buy 16 new manifold studs and 16 new nuts. I pulled 9 of the 16 manifold bolts out with the nuts.
12. The "LX AHC" factor wasn't really an issue for me. I'm sure that by not having the AHC line in the way, it may be easier but I didn't find it a problem for my install.
13. Remember that if you're using factory manifold gaskets, to have the white mark facing OUT towards the manifold.
14. Torque the new header nuts down in a pattern to evenly snug down the header onto the gasket. Personally I start in the middle and work my way out alternating between top and bottom. Don't fully torque the nuts down 1 at a time. Do it in a series of 2-3 passes and snug them down more and more each time until you finally reach your target torque.
15. Lift up an secure the AC line running on the driver side. It is the larger diameter line running right above the new header tube and it can rub and burn through over time. I zip-tied mine to the fuel filter.
16. When you remove the dip stick tube to remove the factory header, plug the hole in the drain pan with a shop towel to prevent debris from falling into your oil pan. I cleaned the area before I removed it to wipe away the debris.
Torque Values - stolen from the TLCFAQ write up but putting them here for completeness. (@RobRed)
-32 ft-lbs on the manifold bolts
-32 ft-lbs on the front O2 sensors.
-14 ft-lbs on the rear O2 sensor nuts
-46 ft-lbs on the manifold to cat flange nuts
-30 ft-lbs on the cat to exhaust flange nuts
-22 ft-lbs on the engine mounting brackets to the frame brackets
Hope this is helpful for those looking to tackle this job! Happy to answer any other questions about my experience if anyone has any. I'll edit this post with anything else I can think of.
I wanted to do a thread detailing my install of my Doug Thorley headers on my 2003 LX470. I haven't seen this much detail anywhere that I could find showing the tools that make this job easier so I hope it will be helpful for someone looking to do this job by themselves. This won't be a how-to per-say but I will share some of the tips and tricks I learned while doing this job as well as some of the tools that I found invaluable! It will also cover some of the things I did wrong that others should keep in mind while doing this job.
I will say that this job was not as daunting as I had originally believed. After all, it's just nuts and bolts, right? (/s)
Amazingly, my stock headers were not cracked but I could have sworn they would be.
What was getting installed...I ordered the DT headers and exhaust from the recent group buy on FB. This will focus on the headers as the exhaust install is very straightforward.
Parts I ordered for the header install. All Toyota OEM parts.
| Manifold Gasket | 1717350021 | 2 | $36.32 | |||
| Front Pipe Gasket | 9008043036 | 2 | $19.34 | |||
| Exhaust Manifold Stud | 9008012008 | 16 | $56.00 | |||
| Exhaust Pipe Lock Nut | 9008017187 | 16 | $24.96 |
Total cost of parts from McGeorge Toyota - $136.62
Tools I used:
I used a lot of various extensions, ratchets, breaker bars, swivels, etc... But these tools listed are ones that not everyone may have on hand but made this job MUCH easier!
1. Flex ratcheting wrenches. I ordered some GearWrench stubby and normal length ratchets which I used extensively as they were great for accessing and snugging down the new manifold nuts in hard to reach areas. I bought these but any good quality flex ratcheting wrenches should work. I had some cheap HF ones previously and the ratcheting mechanism broke on 2 of them in another job I was doing the week before...buy once, buy quality!
Amazon product ASIN B000HBAI40 <-- Stubby wrenches
Amazon product ASIN B07Y49L5PS <-- normal length wrenches
2. Note on spline sockets...I know most people are recommending these to remove the stubborn factory manifold nuts but I did NOT have good luck with them in my experience and stripped two nuts using them. I used my Kobalt 6-pt sockets and they worked great for me on all of the other nuts! Definitely use good quality 6pt sockets as I was exerting A LOT of torque to remove many of the manifold nuts. Don't use 12pt sockets for obvious reasons.
3. Extraction sockets - I tried using some spline sockets to remove the manifold nuts and it stripped two of them. I had to buy some deep extraction sockets to remove them and these worked a treat! The short extraction sockets I had already were not long though to fully seat on the nut. Longer ones pictured below.
Amazon.com - https://www.amazon.com/dp/B083FSBFQ6?psc=1&ref=ppx_yo2_dt_b_product_details
4. Socket depth... I found that my Kobalt 1/2" 14mm socket was the best option for accessibility and seating fully on the manifold nuts to remove them. It is longer than a 3/8" short socket but still long enough to cover the entire manifold stud and nut fully while still being shorter than a deep 3/8" or 1/2" socket. This shows the length difference between the various sockets I had on hand.
5. Swivel sockets - Honestly, I found that the hardest part of this job for me was reinstalling the dip stick tube retaining nut on the driver side. With the new header in, it leaves very little room to access and install the bolt. I used a swivel socket I had in my toolbox which made this easier after trying for way to long to do it by hand or with a 1/4" short socket. After messing with the other methods for the better part of an hour, I got it in with a 1/4" swivel socket in a under a minute fishing through the fender well around the shock mount. Swivel socket I used is pictured below on the far left.
6. Extensions - I found that I had to use a breaker bar and my jack handle as an extension to break 12/16 of the manifold nuts loose. They were well aged in place after 18 years. If you have a "weathered" truck with some corrosion, be prepared for this. I had to bring the extensions outside of the fender to use my jack handle to get enough leverage which required probably ~24-30" or more of extensions to make this work. Have some on hand!
7. E10 socket to install new manifold studs and re-torque any stock ones that didn't pull out with the nut. I had these on hand from my BMW days but get some if you don't have them already.
Picture of the maybe uncommon tools I used. Not including the standard ratchets, extensions, etc.
Tips/Tricks/Lessons Learned:
1. This may be obvious but soak everything in PB blaster for days ahead of time. My truck has minimal if any rust and I had a 1/2 breaker bar with the top of a jack handle for 12 of the 16 header bolts to crack them loose.
2. Take out the catalytic converter pipes for extra working space and to remove the driver side header easier. It's only 2 more bolts and disconnecting the 02 sensor and it made it much easier and allowed for greater accessibility from below. It also makes removing the factory headers and fishing the new ones into place very easy.
3. I didn't remove the steering linkage or heat shield on the driver side like some of the how to's tell you to. I took the shield out with the header and had no problems. I wasted far too much time trying to remove these two things before starting on the driver side header nuts and ended up not needing to remove them at all to do the job.
4. RELEASE AND REROUTE THE O2 SENSOR WIRING HARNESS ON THE PASSENGER SIDE AFTER YOU REMOVE THE STOCK HEADER AND BEFORE YOU PUT THE NEW HEADER BACK IN. Makes it WAY easier to undo since it's virtually inaccessible with the new header installed. I learned this the hard way...
5. Route the passenger side O2 sensor harness ABOVE the header. I did mine below initially and found that it rubbed the header and would melt due to heat. I rerouted it above and have no issues and plenty of clearance. There may be other ways to do this but I found this to be the best way. I released the 2 harness clips and ran the wiring up towards the top of the engine bay and then back down above the collector to the O2 sensor.
6. I used virtually all of the 3/8" and 1/2" extensions, swivels, adapters, ratchets, breaker bars, etc that I had. To get the jack handle and breaker bar outside of the fender to crack many of the bolts loose, I was using ~24-30" of extensions. Use good quality ones that don't flex or have a lot of slack. You need socket swivels to get the socket to seat flush on the manifold bolt or else you don't stand a chance.
7. For access to a couple of manifold nuts, I combined both of my swivels to fully seat the socket on the nut.
8. I loosened (don't completely remove) the trans mount bolts and passenger engine mount bolts to allow engine to flex up high enough to put in a 2x4. I couldn't get mine high enough to get a 2x4 in there without doing this. Be careful not to crack your rad fan shroud when jacking up the engine. I rotated the top fan fins to 11 and 1 o'clock and it was fine. By not fully removing the passenger side and trans mount bolts, you don't have to worry about the engine seating back down in the correct location and having to fight the engine to drop into place when you put it back down.
9. The flex ratcheting wrenches are a life saver. They made this job a lot easier.
10. I removed the air box for easier access to some of the front top manifold bolts on the passenger side. I got a few of the top bolts through the top of the engine bay as it was easier. Removing the air box allows for more space to cycle the ratchet/breaker bar.
11. Buy 16 new manifold studs and 16 new nuts. I pulled 9 of the 16 manifold bolts out with the nuts.
12. The "LX AHC" factor wasn't really an issue for me. I'm sure that by not having the AHC line in the way, it may be easier but I didn't find it a problem for my install.
13. Remember that if you're using factory manifold gaskets, to have the white mark facing OUT towards the manifold.
14. Torque the new header nuts down in a pattern to evenly snug down the header onto the gasket. Personally I start in the middle and work my way out alternating between top and bottom. Don't fully torque the nuts down 1 at a time. Do it in a series of 2-3 passes and snug them down more and more each time until you finally reach your target torque.
15. Lift up an secure the AC line running on the driver side. It is the larger diameter line running right above the new header tube and it can rub and burn through over time. I zip-tied mine to the fuel filter.
16. When you remove the dip stick tube to remove the factory header, plug the hole in the drain pan with a shop towel to prevent debris from falling into your oil pan. I cleaned the area before I removed it to wipe away the debris.
Torque Values - stolen from the TLCFAQ write up but putting them here for completeness. (@RobRed)
-32 ft-lbs on the manifold bolts
-32 ft-lbs on the front O2 sensors.
-14 ft-lbs on the rear O2 sensor nuts
-46 ft-lbs on the manifold to cat flange nuts
-30 ft-lbs on the cat to exhaust flange nuts
-22 ft-lbs on the engine mounting brackets to the frame brackets
Hope this is helpful for those looking to tackle this job! Happy to answer any other questions about my experience if anyone has any. I'll edit this post with anything else I can think of.
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