First off, this isn't a comprehensive DIY - the process is outlined in the workshop manual, but I thought I'd run through the things I found along the way as I haven't seen it covered elsewhere. My truck has always been a bit 'juicy' in the rack gaiters, but started leaking PAS fluid from the pinion input seal in a more significant way a month ago. Not horrendous, but these things only get worse and we're off on a trip to the Alps on Friday. It was also likely to cause it to fail it's MOT (UK annual safety check) tomorrow so needed sorting.
Removing the rack has been covered in a few places (forum.ih8mud.com/threads/how-to-replace-your-own-steering-rack.560104), but as I was planning to rebuild and my inner tie rods/gaiters were good I removed the inner ball joints from the rack shaft to make it shorter, steered the rack full RH. I then lifted the engine off the LH engine mount and my RHD rack came out without touching the oil filter or its housing.
Removing the transfer pipes went okay - I used knipex parallel jaw pliers as they let you really clamp down on the flare nut to prevent slipping.
Next step was to unbolt and remove the pinion housing. That's all the instructions provided by Toyota. I'm sure that's how it works on a nearly new rack or one that lives in CA. However even though my truck is pretty good from a rust PoV the pinion housing was jammed solid. I finally got it out by quickly warming the rack housing up to 100C then rotating the housing fore and aft with plus gas sprayed intermittently into any crack. As the heat in equalised between rack and pinion housing it would become tight again and I'd have to wait for everything to cool and start again. I had to do three heat cycles to get it moving freely enough for the next step. This was the same but with the housing rotated 90deg so I could get the wife to apply a prybar under the flange whilst I wiggled, alternating from side to side to walk the housing up and out. Again this took three heat cycles as everything tightened up as the differential expansion effect wore off.
Hanging on to the pinion housing to rotate it was a challenge as there are no flats and plenty of features that you don't want to damage. I made a giant pin spanner from scraps around the garage. The pins are 8.5mm diameter (turned down from a 10mm bolt), welded into a 12mm chunk of steel that was hacked about to give clearance around the housing. I then welded a ~1m bar to it for leverage. It's not pretty, but it did work. It also made for a good work holding fixture for the next step.
The pinion housing nut needs a special tool. It has to be hollow to clear the pinion, with a 32.5mm 8 sided 3mm deep 'nut' feature to engage with the internal form. I put a 32mm hex on the other end to grab with a socket. This worked a treat.
All of the Teflon rings looked good in my rack (and I didn't have a sizing tool for the new ones) so I left those as is and just resealed with OEM Toyota seals. The only exception to this was the pinion input seal which was on backorder. As I was up against time I ordered a Corteco replacement part - this had the same manufacturer and part number as the OE seal that came out so happy that it's a quality part, even if the manufacturer is NOK!
You'll also need a selection of specifically sized drifts to knock the oil seals out of and in to the pinion housing and rack body. The manual states to press the seals in and out. I did this for the pinion housing, but my press isn't tall enough for the rack housing. Tapping them out and back in with a hammer (carefully) worked fine. I made sure that all tools that went into the cylinder were smooth and burr free to avoid scratches, aluminium where possible and a coating of ATF doesn't hurt either. There's a special tool called out in the instructions for pushing the seals over the rack ends. I just taped up the ends of the rack with electrical tape - there's a taper onto the main part of the shaft, so the tape just protects the seal from the sharp bits at each end and doesn't increase the effect OD and risk stretching the seal.
Reassembly was straightforward and once the corrosion was cleaned out of the pinion housing it slotted straight back in easily (this time with a little grease).
All back on the truck now and no leaks so far.
Removing the rack has been covered in a few places (forum.ih8mud.com/threads/how-to-replace-your-own-steering-rack.560104), but as I was planning to rebuild and my inner tie rods/gaiters were good I removed the inner ball joints from the rack shaft to make it shorter, steered the rack full RH. I then lifted the engine off the LH engine mount and my RHD rack came out without touching the oil filter or its housing.
Removing the transfer pipes went okay - I used knipex parallel jaw pliers as they let you really clamp down on the flare nut to prevent slipping.
Next step was to unbolt and remove the pinion housing. That's all the instructions provided by Toyota. I'm sure that's how it works on a nearly new rack or one that lives in CA. However even though my truck is pretty good from a rust PoV the pinion housing was jammed solid. I finally got it out by quickly warming the rack housing up to 100C then rotating the housing fore and aft with plus gas sprayed intermittently into any crack. As the heat in equalised between rack and pinion housing it would become tight again and I'd have to wait for everything to cool and start again. I had to do three heat cycles to get it moving freely enough for the next step. This was the same but with the housing rotated 90deg so I could get the wife to apply a prybar under the flange whilst I wiggled, alternating from side to side to walk the housing up and out. Again this took three heat cycles as everything tightened up as the differential expansion effect wore off.
Hanging on to the pinion housing to rotate it was a challenge as there are no flats and plenty of features that you don't want to damage. I made a giant pin spanner from scraps around the garage. The pins are 8.5mm diameter (turned down from a 10mm bolt), welded into a 12mm chunk of steel that was hacked about to give clearance around the housing. I then welded a ~1m bar to it for leverage. It's not pretty, but it did work. It also made for a good work holding fixture for the next step.
The pinion housing nut needs a special tool. It has to be hollow to clear the pinion, with a 32.5mm 8 sided 3mm deep 'nut' feature to engage with the internal form. I put a 32mm hex on the other end to grab with a socket. This worked a treat.
All of the Teflon rings looked good in my rack (and I didn't have a sizing tool for the new ones) so I left those as is and just resealed with OEM Toyota seals. The only exception to this was the pinion input seal which was on backorder. As I was up against time I ordered a Corteco replacement part - this had the same manufacturer and part number as the OE seal that came out so happy that it's a quality part, even if the manufacturer is NOK!
You'll also need a selection of specifically sized drifts to knock the oil seals out of and in to the pinion housing and rack body. The manual states to press the seals in and out. I did this for the pinion housing, but my press isn't tall enough for the rack housing. Tapping them out and back in with a hammer (carefully) worked fine. I made sure that all tools that went into the cylinder were smooth and burr free to avoid scratches, aluminium where possible and a coating of ATF doesn't hurt either. There's a special tool called out in the instructions for pushing the seals over the rack ends. I just taped up the ends of the rack with electrical tape - there's a taper onto the main part of the shaft, so the tape just protects the seal from the sharp bits at each end and doesn't increase the effect OD and risk stretching the seal.
Reassembly was straightforward and once the corrosion was cleaned out of the pinion housing it slotted straight back in easily (this time with a little grease).
All back on the truck now and no leaks so far.
